| Title: | Generalized Latent Markov Models |
|---|---|
| Description: | Latent Markov models for longitudinal continuous and categorical data. See Bartolucci, Pandolfi, Pennoni (2017)<doi:10.18637/jss.v081.i04>. |
| Authors: | Francesco Bartolucci [aut, cre], Silvia Pandolfi [aut], Fulvia Pennoni [aut], Alessio Farcomeni [ctb], Alessio Serafini [ctb] |
| Maintainer: | Francesco Bartolucci <[email protected]> |
| License: | GPL (>= 2) |
| Version: | 3.2.3 |
| Built: | 2024-11-06 09:24:15 UTC |
| Source: | CRAN |
The package LMest is a framework for specifying and fitting Latent (or Hidden) Markov (LM) models for the analysis of longitudinal continuous and categorical data. Covariates are also included in the model specification through suitable parameterizations.
Different LM models are estimated through specific functions requiring a data frame in long format. Responses are mainly categorical, the functions referred to continous responses are specified with Cont. When responses are continuos, the (multivariate) Gaussian distribution, conditional to the latent process, is assumed.
The functions are the following:
lmestFunction to estimate LM models for categorical responses generating the following classes:
LMbasic-class for the basic LM model without covariates.
LMmanifest-class for the LM model with covariates in the measurement submodel.
LMlatent-class for the LM model with covariates in the latent model.
lmestContFunction to estimate LM models for continuous outcomes generating the following classes:
LMbasiccont-class for the basic LM model for continuous responses without covariates.
LMlatentcont-class for the LM model for continuous responses with covariates in the latent model.
lmestMixedFunction to estimate Mixed LM models for categorical responses with discrete random effects in the latent model generating the following class:
LMmixed-class for the mixed LM model.
lmestMcFunction to estimate Markov Chain models for categorical responses generating the following classes:
MCbasic-class for the Markov Chain (MC) model without covariates.
MCcov-class for the MC model with covariates.
Maximum likelihood estimation of model parameters is performed through the Expectation-Maximization algorithm, which is implemented by relying on Fortran routines.
Model selection is provided by lmest and lmestCont functions. In addition, function lmestSearch allows us to deal with both model selection and multimodality of the likelihood function. Two main criteria are provided to select the number of latent states: the Akaike Information Criterion and the Bayesian Information Criterion.
Prediction of the latent states is performed by the function lmestDecoding: for local and global decoding (Viterbi algorithm) from the output of functions lmest, lmestCont and lmestMixed.
The package allows us to deal with missing responses, including drop-out and non-monotonic missingness, under the missing-at-random assumption.
Standard errors for the parameter estimates are obtained by the function se through exact computation of the information matrix or by reliable numerical approximations of this matrix.
The print method shows some convergence information, and the summary method shows the estimation results.
The package also provides some real and simulated data sets that are listed using the function data(package = "LMest").
Francesco Bartolucci [aut,cre], Silvia Pandolfi [aut], Fulvia Pennoni [aut], Alessio Farcomeni [ctb], and Alessio Serafini [ctb]
Maintainer: Francesco Bartolucci <[email protected]>
Bartolucci, F., Pandolfi, S. and Pennoni, F. (2017). LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81, 1-38, doi:10.18637/jss.v081.i04.
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013). Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
Bartolucci, F., Farcomeni, A., and Pennoni, F. (2014). Latent Markov models: A review of a general framework for the analysis of longitudinal data with covariates (with discussion). TEST, 23, 433-465.
lmest, lmestCont, lmestMc, lmestMixed, LMmixed-class, LMbasic-class,LMbasiccont-class, LMlatent-class,LMlatentcont-class, LMmanifest-class
Function that performs bootstrap parametric resampling to compute standard errors for the parameter estimates.
bootstrap(est, ...) ## S3 method for class 'LMbasic' bootstrap(est, B = 100, seed = NULL, ...) ## S3 method for class 'LMbasiccont' bootstrap(est, B=100, seed = NULL, ...) ## S3 method for class 'LMlatent' bootstrap(est, B = 100, seed = NULL, ...) ## S3 method for class 'LMlatentcont' bootstrap(est, B = 100, seed = NULL, ...)bootstrap(est, ...) ## S3 method for class 'LMbasic' bootstrap(est, B = 100, seed = NULL, ...) ## S3 method for class 'LMbasiccont' bootstrap(est, B=100, seed = NULL, ...) ## S3 method for class 'LMlatent' bootstrap(est, B = 100, seed = NULL, ...) ## S3 method for class 'LMlatentcont' bootstrap(est, B = 100, seed = NULL, ...)
est |
|
B |
number of bootstrap samples |
seed |
an integer value with the random number generator state |
... |
further arguments |
Average of bootstrap estimates and standard errors for the model parameters in est object.
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
## Not run: # LM model for categorical responses with covariates on the latent model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, tol = 1e-8, start = 1, modBasic = 1, out_se = TRUE, seed = 123) boot1 <- bootstrap(out1) out2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) boot2 <- bootstrap(out2) # LM model for continous responses without covariates data(data_long_cont) out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k =3, modBasic=1, tol=10^-5) boot3 <- bootstrap(out3) # LM model for continous responses with covariates out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output=TRUE) boot4 <- bootstrap(out4) ## End(Not run)## Not run: # LM model for categorical responses with covariates on the latent model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, tol = 1e-8, start = 1, modBasic = 1, out_se = TRUE, seed = 123) boot1 <- bootstrap(out1) out2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) boot2 <- bootstrap(out2) # LM model for continous responses without covariates data(data_long_cont) out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k =3, modBasic=1, tol=10^-5) boot3 <- bootstrap(out3) # LM model for continous responses with covariates out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output=TRUE) boot4 <- bootstrap(out4) ## End(Not run)
Function that performs bootstrap parametric resampling to compute standard errors for the parameter estimates.
The function is no longer maintained. Please look at bootstrap function.
bootstrap_lm_basic(piv, Pi, Psi, n, B = 100, start = 0, mod = 0, tol = 10^-6)bootstrap_lm_basic(piv, Pi, Psi, n, B = 100, start = 0, mod = 0, tol = 10^-6)
piv |
initial probability vector |
Pi |
probability transition matrices (k x k x TT) |
Psi |
matrix of conditional response probabilities (mb x k x r) |
n |
sample size |
B |
number of bootstrap samples |
start |
type of starting values (0 = deterministic, 1 = random) |
mod |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
tol |
tolerance level for convergence |
mPsi |
average of bootstrap estimates of the conditional response probabilities |
mpiv |
average of bootstrap estimates of the initial probability vector |
mPi |
average of bootstrap estimates of the transition probability matrices |
sePsi |
standard errors for the conditional response probabilities |
sepiv |
standard errors for the initial probability vector |
sePi |
standard errors for the transition probability matrices |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # fit of the Basic LM model k <- 3 out1 <- est_lm_basic(S, yv, k, mod = 1, out_se = TRUE) out2 <- bootstrap_lm_basic(out1$piv, out1$Pi, out1$Psi, n, mod = 1, B = 1000) ## End(Not run)## Not run: # Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # fit of the Basic LM model k <- 3 out1 <- est_lm_basic(S, yv, k, mod = 1, out_se = TRUE) out2 <- bootstrap_lm_basic(out1$piv, out1$Pi, out1$Psi, n, mod = 1, B = 1000) ## End(Not run)
Function that performs bootstrap parametric resampling to compute standard errors for the parameter estimates.
The function is no longer maintained. Please look at bootstrap function.
bootstrap_lm_basic_cont(piv, Pi, Mu, Si, n, B = 100, start = 0, mod = 0, tol = 10^-6)bootstrap_lm_basic_cont(piv, Pi, Mu, Si, n, B = 100, start = 0, mod = 0, tol = 10^-6)
piv |
initial probability vector |
Pi |
probability transition matrices (k x k x TT) |
Mu |
matrix of conditional means for the response variables (r x k) |
Si |
var-cov matrix common to all states (r x r) |
n |
sample size |
B |
number of bootstrap samples |
start |
type of starting values (0 = deterministic, 1 = random) |
mod |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
tol |
tolerance level for convergence |
mMu |
average of bootstrap estimates of the conditional means of the response variables |
mSi |
average of bootstrap estimates of the var-cov matrix |
mpiv |
average of bootstrap estimates of the initial probability vector |
mPi |
average of bootstrap estimates of the transition probability matrices |
seMu |
standard errors for the conditional means of the response variables |
seSi |
standard errors for the var-cov matrix |
sepiv |
standard errors for the initial probability vector |
sePi |
standard errors for the transition probability matrices |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2,data_long_cont$Y3)) Y <- res$YY n <- dim(Y)[1] # fit of the Basic LM model for continuous outcomes k <- 3 out1 <- est_lm_basic_cont(Y, k, mod = 1) out2 <- bootstrap_lm_basic_cont(out1$piv, out1$Pi, out1$Mu, out1$Si, n, mod = 1, B = 1000) ## End(Not run)## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2,data_long_cont$Y3)) Y <- res$YY n <- dim(Y)[1] # fit of the Basic LM model for continuous outcomes k <- 3 out1 <- est_lm_basic_cont(Y, k, mod = 1) out2 <- bootstrap_lm_basic_cont(out1$piv, out1$Pi, out1$Mu, out1$Si, n, mod = 1, B = 1000) ## End(Not run)
Function that performs bootstrap parametric resampling to compute standard errors for the parameter estimates.
The function is no longer maintained. Please look at bootstrap function.
bootstrap_lm_cov_latent(X1, X2, param = "multilogit", Psi, Be, Ga, B = 100, fort = TRUE)bootstrap_lm_cov_latent(X1, X2, param = "multilogit", Psi, Be, Ga, B = 100, fort = TRUE)
X1 |
matrix of covariates affecting the initial probabilities (n x nc1) |
X2 |
array of covariates affecting the transition probabilities (n x TT-1 x nc2) |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Psi |
array of conditional response probabilities (mb x k x r) |
Be |
parameters affecting the logit for the initial probabilities |
Ga |
parametes affecting the logit for the transition probabilities |
B |
number of bootstrap samples |
fort |
to use fortran routine when possible (FALSE for not use fortran) |
mPsi |
average of bootstrap estimates of the conditional response probabilities |
mBe |
average of bootstrap estimates of the parameters affecting the logit for the initial probabilities |
mGa |
average of bootstrap estimates of the parameters affecting the logit for the transition probabilities |
sePsi |
standard errors for the conditional response probabilities |
seBe |
standard errors for the parameters in Be |
seGa |
standard errors for the parameters in Ga |
Francesco Bartolucci, Silvia Pandolfi - University of Perugia (IT)
## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model out1 <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, out_se = TRUE) out2 <- bootstrap_lm_cov_latent(X1, X2, Psi = out1$Psi, Be = out1$Be, Ga = out1$Ga, B = 1000) ## End(Not run)## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model out1 <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, out_se = TRUE) out2 <- bootstrap_lm_cov_latent(X1, X2, Psi = out1$Psi, Be = out1$Be, Ga = out1$Ga, B = 1000) ## End(Not run)
Function that performs bootstrap parametric resampling to compute standard errors for the parameter estimates.
The function is no longer maintained. Please look at bootstrap function.
bootstrap_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, B = 100)bootstrap_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, B = 100)
X1 |
matrix of covariates affecting the initial probabilities (n x nc1) |
X2 |
array of covariates affecting the transition probabilities (n x TT-1 x nc2) |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Mu |
matrix of conditional means for the response variables (r x k) |
Si |
var-cov matrix common to all states (r x r) |
Be |
parameters affecting the logit for the initial probabilities |
Ga |
parametes affecting the logit for the transition probabilities |
B |
number of bootstrap samples |
mMu |
average of bootstrap estimates of the conditional means for the response variables |
mSi |
average of bootstrap estimates of the var-cov matrix |
mBe |
average of bootstrap estimates of the parameters affecting the logit for the initial probabilities |
mGa |
average of bootstrap estimates of the parameters affecting the logit for the transition probabilities |
seMu |
standard errors for the conditional means |
seSi |
standard errors for the var-cov matrix |
seBe |
standard errors for the parameters in Be |
seGa |
standard errors for the parameters in Ga |
Francesco Bartolucci, Silvia Pandolfi - University of Perugia (IT)
## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) TT <- 5 res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2,data_long_cont$Y3)) Y <- res$YY X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent_cont(Y, X1, X2, k = 3, output = TRUE) out <- bootstrap_lm_cov_latent_cont(X1, X2, Mu = est$Mu, Si = est$Si, Be = est$Be, Ga = est$Ga, B = 1000) ## End(Not run)## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) TT <- 5 res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2,data_long_cont$Y3)) Y <- res$YY X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent_cont(Y, X1, X2, k = 3, output = TRUE) out <- bootstrap_lm_cov_latent_cont(X1, X2, Mu = est$Mu, Si = est$Si, Be = est$Be, Ga = est$Ga, B = 1000) ## End(Not run)
Simulated dataset about crimes committed by a cohort of subjects.
data(data_criminal_sim)data(data_criminal_sim)
A data frame with 60000 observations on the following 13 variables.
idsubject id
sexgender of the subject
timeoccasion of observation
y1crime of type 1 (violence against the person)
y2crime of type 2 (sexual offences)
y3crime of type 3 (burglary)
y4crime of type 4 (robbery)
y5crime of type 5 (theft and handling stolen goods)
y6crime of type 6 (fraud and forgery)
y7crime of type 7 (criminal demage)
y8crime of type 8 (drug offences)
y9crime of type 9 (motoring offences)
y10crime of type 10 (other offences)
Bartolucci, F., Pennoni, F. and Francis, B. (2007), A latent Markov model for detecting patterns of criminal activity, Journal of the Royal Statistical Society, series A, 170, pp. 115-132.
data(data_criminal_sim)data(data_criminal_sim)
Longitudinal dataset derived from the National Youth Survey about marijuana consumption measured by ordinal variables with 3 categories with increasing levels of consumption (1 "never in the past year", 2 "no more than once in a month in the past year", 3 "more than once a month in the past year").
data(data_drug)data(data_drug)
A data frame with 51 observations on the following 6 variables.
V1reported drug use at the 1st occasion
V2reported drug use at the 2nd occasion
V3reported drug use at the 3rd occasion
V4reported drug use at the 4th occasion
V5reported drug use at the 5th occasion
V6frequency of the response configuration
Elliot, D. S., Huizinga, D. and Menard, S. (1989) Multiple Problem Youth: Delinquency, Substance Use, and Mental Health Problems. New York: Springer.
Bartolucci, F. (2006) Likelihood inference for a class of latent Markov models under linear hypotheses on the transition probabilities. Journal of the Royal Statistical Society, series B, 68, 155-178.
data(data_drug)data(data_drug)
Simulated dataset related to a survey on the employment status of a cohort of graduates.
data(data_employment_sim)data(data_employment_sim)
A data frame with 585 observations on the following variables:
idsubject id.
timeoccasion of observation.
emp0 if unemployed, 1 if employed.
area1 if graduated in the South area, 2 if graduated in the North area.
grade1 if grade at graduation is low, 2 if it is medium, 3 if it is high.
edu1 if parents hold a university degree, 0 if not.
Pennoni, F., Pandolfi, S. and Bartolucci, F. (2024), LMest: An R Package for Estimating Generalized Latent Markov Models, Submitted to the R Journal, pp. 1-30.
data(data_employment_sim)data(data_employment_sim)
Simulated longitudinal dataset coming from a medical study to assess the health state progression of patients after a certain treatment.
data(data_heart_sim)data(data_heart_sim)
A data frame referred to 125 units observed at 6 time occasions on the following variables:
idsubject id
timeoccasion of observation
sapsystolic arterial pressure in mmgh
dapdiastolic arterial pressure in mmgh
hrheart rate in bpm
fluidfluid administration in ml/kg/h
gender1 for male, 2 for females
ageage in years
Pennoni, F., Pandolfi, S. and Bartolucci, F. (2024), LMest: An R Package for Estimating Generalized Latent Markov Models, Submitted to the R Journal, pp. 1-30.
data(data_heart_sim)data(data_heart_sim)
Simulated multivariate longitudinal continuous dataset assuming that there are 500 subjects in the study whose data are collected at 5 equally-spaced time points.
data(data_long_cont)data(data_long_cont)
A data frame with 2500 observations on the following 7 variables.
idsubject id.
timeoccasion of observation.
Y1a numeric vector for the first longitudinal response.
Y2a numeric vector for the second longitudinal response.
Y3a numeric vector for the third longitudinal response.
X1a numeric vector for the first covariate.
X2a numeric vector for the second covariate.
data(data_long_cont)data(data_long_cont)
Simulated dataset related to customers of four different brands along with the prices of each transaction.
data(data_market_sim)data(data_market_sim)
A data frame with 200 observations on the following variables:
idsubject id.
timeoccasion of observation.
brand0 if the customer has purchased the product from brand A, 1 if brand B, 2 if brand C, 3 if brand D.
price0 if the price of the transaction is in the range [0.1, 10], 1 if it is in (10, 30], 2 if it is in (30, 60], 3 if it is in (30, 100], 4 if it is in (100, 500] (in thousands of Euros).
ageage of the customer in years
incomeincome declared by the customer at the time of the first purchase (in thousands of Euros).
Pennoni, F., Pandolfi, S. and Bartolucci, F. (2024), LMest: An R Package for Estimating Generalized Latent Markov Models, Submitted to the R Journal, pp. 1-30.
data(data_market_sim)data(data_market_sim)
Dataset about self-reported health status derived from the Health and Retirement Study conducted by the University of Michigan.
data(data_SRHS_long)data(data_SRHS_long)
A data frame with 56592 observations on the following 6 variables.
toccasion of observation
idsubject id
gendersex of the subject coded as 1 for "male", 2 for "female"
racerace coded as 1 for "white", 2 for "black", 3 for "others"
educationeducational level coded as 1 for "high school", 2 for "general educational diploma", 3 for "high school graduate", 4 for "some college", 5 for "college and above"
ageage at the different time occasions
srhsself-reported health status at the different time occasions coded as 1 for "excellent", 2 for "very good", 3 for "good", 4 for "fair", 5 for "poor"
Bartolucci, F., Bacci, S. and Pennoni, F. (2014) Longitudinal analysis of the self-reported health status by mixture latent autoregressive models, Journal of the Royal Statistical Society - series C, 63, pp. 267-288
data(data_SRHS_long)data(data_SRHS_long)
Function that performs local and global decoding (Viterbi) from the output of est_lm_basic, est_lm_cov_latent, est_lm_cov_manifest, and est_lm_mixed.
The function is no longer maintained. Please look at lmestDecoding function
decoding(est, Y, X1 = NULL, X2 = NULL, fort = TRUE)decoding(est, Y, X1 = NULL, X2 = NULL, fort = TRUE)
est |
output from |
Y |
single vector or matrix of responses |
X1 |
matrix of covariates on the initial probabilities ( |
X2 |
array of covariates on the transition probabilites |
fort |
to use Fortran routines |
Ul |
matrix of local decoded states corresponding to each row of Y |
Ug |
matrix of global decoded states corresponding to each row of Y |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
Viterbi A. (1967) Error Bounds for Convolutional Codes and an Asymptotically Optimum Decoding Algorithm. IEEE Transactions on Information Theory, 13, 260-269.
Juan B., Rabiner L. (1991) Hidden Markov Models for Speech Recognition. Technometrics, 33, 251-272.
## Not run: # example for the output from est_lm_basic data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # fit the Basic LM model k <- 3 est <- est_lm_basic(S, yv, k, mod = 1) # decoding for a single sequence out1 <- decoding(est, S[1,]) # decoding for all sequences out2 <- decoding(est, S) # example for the output from est_lm_cov_latent with difflogit parametrization data(data_SRHS_long) dataSRHS <- data_SRHS_long[1:1600,] TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50,(dataSRHS$age-50)^2/100), Y= dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, param = "difflogit") # decoding for a single sequence out1 <- decoding(est, S[1,,], X1[1,], X2[1,,]) # decoding for all sequences out2 <- decoding(est, S, X1, X2) ## End(Not run)## Not run: # example for the output from est_lm_basic data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # fit the Basic LM model k <- 3 est <- est_lm_basic(S, yv, k, mod = 1) # decoding for a single sequence out1 <- decoding(est, S[1,]) # decoding for all sequences out2 <- decoding(est, S) # example for the output from est_lm_cov_latent with difflogit parametrization data(data_SRHS_long) dataSRHS <- data_SRHS_long[1:1600,] TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50,(dataSRHS$age-50)^2/100), Y= dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, param = "difflogit") # decoding for a single sequence out1 <- decoding(est, S[1,,], X1[1,], X2[1,,]) # decoding for all sequences out2 <- decoding(est, S, X1, X2) ## End(Not run)
Draw a sample for LMest objects of classes: LMbasic, LMbasiccont, LMlatent, LMlatentcont, and LMmixed
## S3 method for class 'LMbasic' draw(est, n = NULL, TT = NULL, format = c("long","matrices"), seed = NULL, ...) ## S3 method for class 'LMlatent' draw(est, n = NULL, TT = NULL, data, index, format = c("long", "matrices"), fort = TRUE, seed = NULL, ...) ## S3 method for class 'LMbasiccont' draw(est, n = NULL, TT = NULL, format = c("long","matrices"), seed = NULL, ...) ## S3 method for class 'LMlatentcont' draw(est, n = NULL , TT = NULL, data, index, format = c("long", "matrices"), fort = TRUE, seed = NULL, ...) ## S3 method for class 'LMmixed' draw(est, n = NULL, TT = NULL, format = c("long", "matrices"), seed = NULL, ...)## S3 method for class 'LMbasic' draw(est, n = NULL, TT = NULL, format = c("long","matrices"), seed = NULL, ...) ## S3 method for class 'LMlatent' draw(est, n = NULL, TT = NULL, data, index, format = c("long", "matrices"), fort = TRUE, seed = NULL, ...) ## S3 method for class 'LMbasiccont' draw(est, n = NULL, TT = NULL, format = c("long","matrices"), seed = NULL, ...) ## S3 method for class 'LMlatentcont' draw(est, n = NULL , TT = NULL, data, index, format = c("long", "matrices"), fort = TRUE, seed = NULL, ...) ## S3 method for class 'LMmixed' draw(est, n = NULL, TT = NULL, format = c("long", "matrices"), seed = NULL, ...)
est |
object of class |
n |
sample size |
format |
character string indicating the format of final responses matrix |
seed |
an integer value with the random number generator state |
data |
a data frame in long format, with rows corresponding to observations and columns corresponding to covariates, a column corresponding to time occasions and a column containing the unit identifier when est is of class |
index |
a character vector with two elements indicating the name of the "id" column as first element and the "time" column as second element when est is of class |
fort |
to use fortran routine when possible (FALSE for not use fortran) when est is of class |
TT |
number of time occasions when est is of class |
... |
further arguments |
Y |
matrix of response configurations unit by unit when est is of class |
S |
matrix of distinct response configurations when est is of class |
yv |
corresponding vector of frequencies when est is of class |
piv |
vector of initial probabilities of the latent Markov chain when est is of class |
Pi |
set of transition probabilities matrices (k x k x TT) when est is of class |
Psi |
array of conditional response probabitlies (mb x k x r)when est is of class |
n |
sample size |
TT |
number of time occasions |
est |
object of class |
U |
matrix containing the sequence of latent states (n x TT) when est is of class |
Psi |
array of conditional response probabilities (mb x k x r) when est is of class |
Be |
parameters affecting the logit for the initial probabilities when est is of class |
Ga |
parametes affecting the logit for the transition probabilitieswhen est is of class |
latentFormula |
a symbolic description of the model to be fitted when est is of class |
data |
a data frame in long format, with rows corresponding to observations and columns corresponding to variables, a column corresponding to time occasions and a column containing the unit identifier when est is of class |
Mu |
array of conditional means for the response variables (r x k) when est is of class |
Si |
var-cov matrix common to all states (r x r) when est is of class |
latentFormula |
a symbolic description of the model to be fitted. A detailed description is given in |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni
## Not run: # draw a sample for 1000 units and only one response variable when est is of class LMbasic n <- 1000 TT <- 6 k <- 2 r <- 1 #number of response variables mb <- 3 #maximum number of response categories piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Psi <- matrix(c(0.7,0.2,0.1,0.5,0.4,0.1), mb, k) Psi <- array(Psi, c(mb, k, r)) est = list(piv=piv, Pi=Pi, Psi=Psi, n=n, TT=TT) class(est) = "LMbasic" out <- draw(est) data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] SRHS$srhs <- 5 - SRHS$srhs est <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3) out1 <- draw(est = est, format = "matrices", seed = 4321, n = 100) # draw a sample for 7074 units and only one response variable when est is of class LMlatent data(data_SRHS_long) data_SRHS_long$srhs <- 5 - data_SRHS_long$srhs n <- length(unique(data_SRHS_long$id)) TT <- max(data_SRHS_long$t) est <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = data_SRHS_long, k = 2, paramLatent = "multilogit", start = 0) out <- draw(est = est, data = data_SRHS_long, index = c("id","t"), format = "matrices",seed = 4321) est1 = list(Psi = est$Psi, Be = est$Be, Ga = est$Ga, paramLatent = "multilogit",n=n,TT=TT) attributes(est1)$latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100) class(est1) = "LMlatent" out1 <- draw(est = est1, data = data_SRHS_long, index = c("id","t"), format = "matrices", seed = 4321) # draw a sample for 1000 units and 3 response variable when est is of class LMbasiccont n <- 1000 TT <- 5 k <- 2 r <- 3 #number of response variables piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) est = list(piv=piv,Pi=Pi,Mu=Mu,Si=Si,n=n,TT=TT) class(est) = "LMbasiccont" out <- draw(est) data(data_long_cont) est <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 3, modBasic = 1, tol = 10^-5) out2 <- draw(est = est, n = 100, format = "long", seed = 4321) # draw a sample for 1000 units and 3 response variable when est is of class LMlatentcont data(data_long_cont) est <- lmestCont(responsesFormula = Y1 + Y2 + Y3~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3) out <- draw(est = est, data = data_long_cont, index = c("id", "time"), format = "matrices", seed = 4321) est1 <- list(Mu = est$Mu,Si = est$Si,Be = est$Be,Ga = est$Ga,paramLatent="multilogit",n=est$n, TT=est$TT) attributes(est1)$latentFormula = ~ X1 + X2 class(est1) = "LMlatentcont" out1 <- draw(est = est1, data = data_long_cont, index = c("id", "time"), fort=TRUE, seed = 4321, format = "matrices") ## End(Not run) # draw a sample for 1000 units and only one response variable and 5 time occasions # when est if of class LMmixed k1 <- 2 k2 <- 3 la <- rep(1/k1, k1) Piv <- matrix(1/k2, k2, k1) Pi <- array(0, c(k2, k2, k1)) Pi[,,1] <- diag(k2) Pi[,,2] <- 1/k2 Psi <- cbind(c(0.6,0.3,0.1), c(0.1,0.3,0.6), c(0.3,0.6,0.1)) est <- list(la=la, Piv=Piv, Pi=Pi, Psi=Psi, n=1000,TT=5) class(est) = "LMmixed" out <- draw(est = est) ## Not run: # Example based on criminal data when est if of class LMmixed data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) # Estimate mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula est <- lmestMixed(responsesFormula = responsesFormula, index = c("id","time"), k1 = 2, k2 = 2, data = data_criminal_sim[data_criminal_sim$sex == 2,]) out <- draw(est = est, n = 100, TT = 6, seed = 4321) ## End(Not run)## Not run: # draw a sample for 1000 units and only one response variable when est is of class LMbasic n <- 1000 TT <- 6 k <- 2 r <- 1 #number of response variables mb <- 3 #maximum number of response categories piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Psi <- matrix(c(0.7,0.2,0.1,0.5,0.4,0.1), mb, k) Psi <- array(Psi, c(mb, k, r)) est = list(piv=piv, Pi=Pi, Psi=Psi, n=n, TT=TT) class(est) = "LMbasic" out <- draw(est) data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] SRHS$srhs <- 5 - SRHS$srhs est <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3) out1 <- draw(est = est, format = "matrices", seed = 4321, n = 100) # draw a sample for 7074 units and only one response variable when est is of class LMlatent data(data_SRHS_long) data_SRHS_long$srhs <- 5 - data_SRHS_long$srhs n <- length(unique(data_SRHS_long$id)) TT <- max(data_SRHS_long$t) est <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = data_SRHS_long, k = 2, paramLatent = "multilogit", start = 0) out <- draw(est = est, data = data_SRHS_long, index = c("id","t"), format = "matrices",seed = 4321) est1 = list(Psi = est$Psi, Be = est$Be, Ga = est$Ga, paramLatent = "multilogit",n=n,TT=TT) attributes(est1)$latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100) class(est1) = "LMlatent" out1 <- draw(est = est1, data = data_SRHS_long, index = c("id","t"), format = "matrices", seed = 4321) # draw a sample for 1000 units and 3 response variable when est is of class LMbasiccont n <- 1000 TT <- 5 k <- 2 r <- 3 #number of response variables piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) est = list(piv=piv,Pi=Pi,Mu=Mu,Si=Si,n=n,TT=TT) class(est) = "LMbasiccont" out <- draw(est) data(data_long_cont) est <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 3, modBasic = 1, tol = 10^-5) out2 <- draw(est = est, n = 100, format = "long", seed = 4321) # draw a sample for 1000 units and 3 response variable when est is of class LMlatentcont data(data_long_cont) est <- lmestCont(responsesFormula = Y1 + Y2 + Y3~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3) out <- draw(est = est, data = data_long_cont, index = c("id", "time"), format = "matrices", seed = 4321) est1 <- list(Mu = est$Mu,Si = est$Si,Be = est$Be,Ga = est$Ga,paramLatent="multilogit",n=est$n, TT=est$TT) attributes(est1)$latentFormula = ~ X1 + X2 class(est1) = "LMlatentcont" out1 <- draw(est = est1, data = data_long_cont, index = c("id", "time"), fort=TRUE, seed = 4321, format = "matrices") ## End(Not run) # draw a sample for 1000 units and only one response variable and 5 time occasions # when est if of class LMmixed k1 <- 2 k2 <- 3 la <- rep(1/k1, k1) Piv <- matrix(1/k2, k2, k1) Pi <- array(0, c(k2, k2, k1)) Pi[,,1] <- diag(k2) Pi[,,2] <- 1/k2 Psi <- cbind(c(0.6,0.3,0.1), c(0.1,0.3,0.6), c(0.3,0.6,0.1)) est <- list(la=la, Piv=Piv, Pi=Pi, Psi=Psi, n=1000,TT=5) class(est) = "LMmixed" out <- draw(est = est) ## Not run: # Example based on criminal data when est if of class LMmixed data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) # Estimate mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula est <- lmestMixed(responsesFormula = responsesFormula, index = c("id","time"), k1 = 2, k2 = 2, data = data_criminal_sim[data_criminal_sim$sex == 2,]) out <- draw(est = est, n = 100, TT = 6, seed = 4321) ## End(Not run)
Function that draws samples from the basic LM model with specific parameters.
The function is no longer maintained. Please look at draw.LMbasic function.
draw_lm_basic(piv, Pi, Psi, n)draw_lm_basic(piv, Pi, Psi, n)
piv |
vector of initial probabilities of the latent Markov chain |
Pi |
set of transition probabilities matrices (k x k x TT) |
Psi |
array of conditional response probabitlies (mb x k x r) |
n |
sample size |
Y |
matrix of response configurations unit by unit |
S |
matrix of distinct response configurations |
yv |
corresponding vector of frequencies |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # draw a sample for 1000 units and only one response variable n <- 1000 TT <- 6 k <- 2 r <- 1 #number of response variables mb <- 3 #maximum number of response categories piv <- c(0.7, 0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Psi <- matrix(c(0.7,0.2,0.1,0.5,0.4,0.1), mb, k) Psi <- array(Psi, c(mb, k, r)) out <- draw_lm_basic(piv, Pi, Psi, n = 1000) ## End(Not run)## Not run: # draw a sample for 1000 units and only one response variable n <- 1000 TT <- 6 k <- 2 r <- 1 #number of response variables mb <- 3 #maximum number of response categories piv <- c(0.7, 0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Psi <- matrix(c(0.7,0.2,0.1,0.5,0.4,0.1), mb, k) Psi <- array(Psi, c(mb, k, r)) out <- draw_lm_basic(piv, Pi, Psi, n = 1000) ## End(Not run)
Function that draws samples from the basic LM model for continuous outcomes with specific parameters.
The function is no longer maintained. Please look at draw.LMbasiccont function.
draw_lm_basic_cont(piv, Pi, Mu, Si, n)draw_lm_basic_cont(piv, Pi, Mu, Si, n)
piv |
vector of initial probabilities of the latent Markov chain |
Pi |
set of transition probabilities matrices (k x k x TT) |
Mu |
matrix of conditional means for the response variables (r x k) |
Si |
var-cov matrix common to all states (r x r) |
n |
sample size |
Y |
array of continuous outcomes (n x TT x r) |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # draw a sample for 1000 units and 3 response variable n <- 1000 TT <- 5 k <- 2 r <- 3 #number of response variables piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) out <- draw_lm_basic_cont(piv, Pi, Mu, Si, n) ## End(Not run)## Not run: # draw a sample for 1000 units and 3 response variable n <- 1000 TT <- 5 k <- 2 r <- 3 #number of response variables piv <- c(0.7,0.3) Pi <- matrix(c(0.9,0.1,0.1,0.9), k, k) Pi <- array(Pi, c(k, k, TT)) Pi[,,1] <- 0 Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) out <- draw_lm_basic_cont(piv, Pi, Mu, Si, n) ## End(Not run)
Function that draws samples from the LM model with individual covariates with specific parameters.
The function is no longer maintained. Please look at draw.LMlatent function.
draw_lm_cov_latent(X1, X2, param = "multilogit", Psi, Be, Ga, fort = TRUE)draw_lm_cov_latent(X1, X2, param = "multilogit", Psi, Be, Ga, fort = TRUE)
X1 |
desing matrix for the covariates on the initial probabilities (n x nc1) |
X2 |
desing matrix for the covariates on the transition probabilities (n x TT-1 x nc2) |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Psi |
array of conditional response probabilities (mb x k x r) |
Be |
parameters affecting the logit for the initial probabilities |
Ga |
parametes affecting the logit for the transition probabilities |
fort |
to use fortran routine when possible (FALSE for not use fortran) |
Y |
matrix of response configurations unit by unit (n x TT x r) |
U |
matrix containing the sequence of latent states (n x TT) |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # draw a sample for 1000 units, 10 response variable and 2 covariates n <- 1000 TT <- 5 k <- 2 nc <- 2 #number of covariates r <- 10 #number of response variables mb <- 2 #maximum number of response categories fort <- TRUE Psi <- matrix(c(0.9,0.1,0.1,0.9), mb, k) Psi <- array(Psi, c(mb, k, r)) Ga <- matrix(c(-log(0.9/0.1),0.5,1), (nc+1)*(k-1), k) Be <- array(c(0,0.5,1), (nc+1)*(k-1)) #Simulate covariates X1 <- matrix(0, n, nc) for(j in 1:nc) X1[,j] <- rnorm(n) X2 <- array(0,c(n, TT-1, nc)) for (t in 1:(TT-1)) for(j in 1:nc){ if(t==1){ X2[,t,j] <- 0.5*X1[,j] + rnorm(n) }else{ X2[,t,j] <- 0.5 *X2[,t-1,j] + rnorm(n) } } out <- draw_lm_cov_latent(X1, X2, Psi = Psi, Be = Be, Ga = Ga, fort = fort) ## End(Not run)## Not run: # draw a sample for 1000 units, 10 response variable and 2 covariates n <- 1000 TT <- 5 k <- 2 nc <- 2 #number of covariates r <- 10 #number of response variables mb <- 2 #maximum number of response categories fort <- TRUE Psi <- matrix(c(0.9,0.1,0.1,0.9), mb, k) Psi <- array(Psi, c(mb, k, r)) Ga <- matrix(c(-log(0.9/0.1),0.5,1), (nc+1)*(k-1), k) Be <- array(c(0,0.5,1), (nc+1)*(k-1)) #Simulate covariates X1 <- matrix(0, n, nc) for(j in 1:nc) X1[,j] <- rnorm(n) X2 <- array(0,c(n, TT-1, nc)) for (t in 1:(TT-1)) for(j in 1:nc){ if(t==1){ X2[,t,j] <- 0.5*X1[,j] + rnorm(n) }else{ X2[,t,j] <- 0.5 *X2[,t-1,j] + rnorm(n) } } out <- draw_lm_cov_latent(X1, X2, Psi = Psi, Be = Be, Ga = Ga, fort = fort) ## End(Not run)
Function that draws samples from the LM model for continuous outcomes with individual covariates with specific parameters.
The function is no longer maintained. Please look at draw.LMlatentcont function.
draw_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, fort = TRUE)draw_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, fort = TRUE)
X1 |
desing matrix for the covariates on the initial probabilities (n x nc1) |
X2 |
desing matrix for the covariates on the transition probabilities (n x TT-1 x nc2) |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Mu |
array of conditional means for the response variables (r x k) |
Si |
var-cov matrix common to all states (r x r) |
Be |
parameters affecting the logit for the initial probabilities |
Ga |
parametes affecting the logit for the transition probabilities |
fort |
to use fortran routine when possible (FALSE for not use fortran) |
Y |
array of continuous outcomes (n x TT x r) |
U |
matrix containing the sequence of latent states (n x TT) |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # draw a sample for 1000 units, 10 response variable and 2 covariates n <- 1000 TT <- 5 k <- 2 nc <- 2 #number of covariates r <- 3 #number of response variables fort <- TRUE Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) Ga <- matrix(c(-log(0.9/0.1),0.5,1), (nc+1)*(k-1), k) Be <- array(c(0,0.5,1), (nc+1)*(k-1)) #Simulate covariates X1 <- matrix(0, n, nc) for(j in 1:nc) X1[,j] <- rnorm(n) X2 <- array(0, c(n,TT-1,nc)) for (t in 1:(TT-1)) for(j in 1:nc){ if(t==1){ X2[,t,j] <- 0.5*X1[,j] + rnorm(n) }else{ X2[,t,j] <- 0.5*X2[,t-1,j] + rnorm(n) } } out <- draw_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, fort = fort) ## End(Not run)## Not run: # draw a sample for 1000 units, 10 response variable and 2 covariates n <- 1000 TT <- 5 k <- 2 nc <- 2 #number of covariates r <- 3 #number of response variables fort <- TRUE Mu <- matrix(c(-2,-2,0,0,2,2), r, k) Si <- diag(r) Ga <- matrix(c(-log(0.9/0.1),0.5,1), (nc+1)*(k-1), k) Be <- array(c(0,0.5,1), (nc+1)*(k-1)) #Simulate covariates X1 <- matrix(0, n, nc) for(j in 1:nc) X1[,j] <- rnorm(n) X2 <- array(0, c(n,TT-1,nc)) for (t in 1:(TT-1)) for(j in 1:nc){ if(t==1){ X2[,t,j] <- 0.5*X1[,j] + rnorm(n) }else{ X2[,t,j] <- 0.5*X2[,t-1,j] + rnorm(n) } } out <- draw_lm_cov_latent_cont(X1, X2, param = "multilogit", Mu, Si, Be, Ga, fort = fort) ## End(Not run)
Function that draws samples from the mixed LM model with specific parameters.
The function is no longer maintained. Please look at draw.LMmixed function.
draw_lm_mixed(la, Piv, Pi, Psi, n, TT)draw_lm_mixed(la, Piv, Pi, Psi, n, TT)
la |
vector of mass probabilities for the first latent variable |
Piv |
matrix of initial probabilities of the latent Markov chain (k2 x k1) |
Pi |
set of transition matrices (k2 x k2 x k1) |
Psi |
array of conditional response probabitlies (mb x k2 x r) |
n |
sample size |
TT |
number of time occasions |
Y |
matrix of response configurations unit by unit |
S |
matrix of distinct response configurations |
yv |
corresponding vector of frequencies |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # draw a sample for 1000 units and only one response variable and 5 time occasions k1 <- 2 k2 <- 3 la <- rep(1/k1,k1) Piv <- matrix(1/k2,k2,k1) Pi <- array(0,c(k2,k2,k1)) Pi[,,1] <- diag(k2) Pi[,,2] <- 1/k2 Psi <- cbind(c(0.6,0.3,0.1),c(0.1,0.3,0.6),c(0.3,0.6,0.1)) out <- draw_lm_mixed(la,Piv,Pi,Psi,n=1000,TT=5) ## End(Not run)## Not run: # draw a sample for 1000 units and only one response variable and 5 time occasions k1 <- 2 k2 <- 3 la <- rep(1/k1,k1) Piv <- matrix(1/k2,k2,k1) Pi <- array(0,c(k2,k2,k1)) Pi[,,1] <- diag(k2) Pi[,,2] <- 1/k2 Psi <- cbind(c(0.6,0.3,0.1),c(0.1,0.3,0.6),c(0.3,0.6,0.1)) out <- draw_lm_mixed(la,Piv,Pi,Psi,n=1000,TT=5) ## End(Not run)
Main function for estimating the basic LM model.
The function is no longer maintained. Please look at lmest function.
est_lm_basic(S, yv, k, start = 0, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, piv = NULL, Pi = NULL, Psi = NULL)est_lm_basic(S, yv, k, start = 0, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, piv = NULL, Pi = NULL, Psi = NULL)
S |
array of available configurations (n x TT x r) with categories starting from 0 (use NA for missing responses) |
yv |
vector of frequencies of the available configurations |
k |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
mod |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors |
piv |
initial value of the initial probability vector (if start=2) |
Pi |
initial value of the transition probability matrices (k x k x TT) (if start=2) |
Psi |
initial value of the conditional response probabilities (mb x k x r) (if start=2) |
lk |
maximum log-likelihood |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices |
Psi |
estimate of conditional response probabilities |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
lkv |
log-likelihood trace at every step |
V |
array containing the posterior distribution of the latent states for each response configuration and time occasion |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
sePsi |
standard errors for the conditional response probabilities |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] # fit of the Basic LM model k <- 3 out <- est_lm_basic(S, yv, k, mod = 1) summary(out) # Example based on criminal data # load criminal data data(data_criminal_sim) out <- long2wide(data_criminal_sim, "id" , "time" , "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"),aggr = T, full = 999) XX <- out$XX YY <- out$YY freq <- out$freq # fit basic LM model with increasing number of states to select the most suitable Res0 <- vector("list", 7) for(k in 1:7){ Res0[[k]] <- est_lm_basic(YY, freq, k, mod = 1, tol = 10^-4) save(list <- ls(), file = "example_criminal_temp.RData") } out1 <- Res0[[6]] ## End(Not run)## Not run: # Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] # fit of the Basic LM model k <- 3 out <- est_lm_basic(S, yv, k, mod = 1) summary(out) # Example based on criminal data # load criminal data data(data_criminal_sim) out <- long2wide(data_criminal_sim, "id" , "time" , "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"),aggr = T, full = 999) XX <- out$XX YY <- out$YY freq <- out$freq # fit basic LM model with increasing number of states to select the most suitable Res0 <- vector("list", 7) for(k in 1:7){ Res0[[k]] <- est_lm_basic(YY, freq, k, mod = 1, tol = 10^-4) save(list <- ls(), file = "example_criminal_temp.RData") } out1 <- Res0[[6]] ## End(Not run)
Main function for estimating the basic LM model for continuous outcomes.
The function is no longer maintained. Please look at lmestCont function.
est_lm_basic_cont(Y, k, start = 0, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, piv = NULL, Pi = NULL, Mu = NULL, Si = NULL)est_lm_basic_cont(Y, k, start = 0, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, piv = NULL, Pi = NULL, Mu = NULL, Si = NULL)
Y |
array of continuous outcomes (n x TT x r) |
k |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
mod |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors |
piv |
initial value of the initial probability vector (if start=2) |
Pi |
initial value of the transition probability matrices (k x k x TT) (if start=2) |
Mu |
initial value of the conditional means (r x k) (if start=2) |
Si |
initial value of the var-cov matrix common to all states (r x r) (if start=2) |
lk |
maximum log-likelihood |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices |
Mu |
estimate of conditional means of the response variables |
Si |
estimate of var-cov matrix common to all states |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
lkv |
log-likelihood trace at every step |
V |
array containing the posterior distribution of the latent states for each units and time occasion |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) res <- long2matrices(data_long_cont$id,X=cbind(data_long_cont$X1,data_long_cont$X2), Y=cbind(data_long_cont$Y1, data_long_cont$Y2, data_long_cont$Y3)) Y <- res$YY # fit of the Basic LM model for continuous outcomes k <- 3 out <- est_lm_basic_cont(Y, k, mod = 1, tol = 10^-5) summary(out) ## End(Not run)## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) res <- long2matrices(data_long_cont$id,X=cbind(data_long_cont$X1,data_long_cont$X2), Y=cbind(data_long_cont$Y1, data_long_cont$Y2, data_long_cont$Y3)) Y <- res$YY # fit of the Basic LM model for continuous outcomes k <- 3 out <- est_lm_basic_cont(Y, k, mod = 1, tol = 10^-5) summary(out) ## End(Not run)
Main function for estimating the LM model with covariates in the latent model.
The function is no longer maintained. Please look at lmest function.
est_lm_cov_latent(S, X1=NULL, X2=NULL, yv = rep(1,nrow(S)), k, start = 0, tol = 10^-8, maxit = 1000, param = "multilogit", Psi, Be, Ga, fort = TRUE, output = FALSE, out_se = FALSE, fixPsi = FALSE)est_lm_cov_latent(S, X1=NULL, X2=NULL, yv = rep(1,nrow(S)), k, start = 0, tol = 10^-8, maxit = 1000, param = "multilogit", Psi, Be, Ga, fort = TRUE, output = FALSE, out_se = FALSE, fixPsi = FALSE)
S |
array of available configurations (n x TT x r) with categories starting from 0 (use NA for missing responses) |
X1 |
matrix of covariates affecting the initial probabilities (n x nc1) |
X2 |
array of covariates affecting the transition probabilities (n x TT-1 x nc2) |
yv |
vector of frequencies of the available configurations |
k |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
tol |
tolerance level for checking convergence of the algorithm |
maxit |
maximum number of iterations of the algorithm |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Psi |
intial value of the array of the conditional response probabilities (mb x k x r) |
Be |
intial value of the parameters affecting the logit for the initial probabilities (if start=2) |
Ga |
intial value of the parametes affecting the logit for the transition probabilities (if start=2) |
fort |
to use fortran routine when possible (FALSE for not use fortran) |
output |
to return additional output (V,PI,Piv,Ul) |
out_se |
to compute the information matrix and standard errors |
fixPsi |
TRUE if Psi is given in input and is not updated anymore |
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
Piv |
estimate of initial probability matrix |
PI |
estimate of transition probability matrices |
Psi |
estimate of conditional response probabilities |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
lkv |
log-likelihood trace at every step |
V |
array containing the posterior distribution of the latent states for each response configuration and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
sePsi |
standard errors for the conditional response matrix |
seBe |
standard errors for Be |
seGa |
standard errors for Ga |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia, http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS = data_SRHS_long TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY n <- dim(S)[1] # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est2f <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, out_se = TRUE) summary(est2f) # average transition probability matrix PI <- round(apply(est2f$PI[,,,2:TT], c(1,2), mean), 4) # Transition probability matrix for white females with high educational level ind1 <- X1[,1] == 1 & X1[,2] == 0 & X1[,4] == 1) PI1 <- round(apply(est2f$PI[,,ind1,2:TT], c(1,2), mean), 4) # Transition probability matrix for non-white male, low educational level ind2 <- (X1[,1] == 0 & X1[,2] == 1 & X1[,3] == 0 & X1[,4] == 0) PI2 <- round(apply(est2f$PI[,,ind2,2:TT], c(1,2), mean), 4) ## End(Not run)## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS = data_SRHS_long TT <- 8 head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) # matrix of responses (with ordered categories from 0 to 4) S <- 5-res$YY n <- dim(S)[1] # matrix of covariates (for the first and the following occasions) # colums are: gender,race,educational level (2 columns),age,age^2) X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est2f <- est_lm_cov_latent(S, X1, X2, k = 2, output = TRUE, out_se = TRUE) summary(est2f) # average transition probability matrix PI <- round(apply(est2f$PI[,,,2:TT], c(1,2), mean), 4) # Transition probability matrix for white females with high educational level ind1 <- X1[,1] == 1 & X1[,2] == 0 & X1[,4] == 1) PI1 <- round(apply(est2f$PI[,,ind1,2:TT], c(1,2), mean), 4) # Transition probability matrix for non-white male, low educational level ind2 <- (X1[,1] == 0 & X1[,2] == 1 & X1[,3] == 0 & X1[,4] == 0) PI2 <- round(apply(est2f$PI[,,ind2,2:TT], c(1,2), mean), 4) ## End(Not run)
Main function for estimating the LM model for continuous outcomes with covariates in the latent model.
The function is no longer maintained. Please look at lmestCont function.
est_lm_cov_latent_cont(Y, X1 = NULL, X2 = NULL, yv = rep(1,nrow(Y)), k, start = 0, tol = 10^-8, maxit = 1000, param = "multilogit", Mu = NULL, Si = NULL, Be = NULL, Ga = NULL, output = FALSE, out_se = FALSE)est_lm_cov_latent_cont(Y, X1 = NULL, X2 = NULL, yv = rep(1,nrow(Y)), k, start = 0, tol = 10^-8, maxit = 1000, param = "multilogit", Mu = NULL, Si = NULL, Be = NULL, Ga = NULL, output = FALSE, out_se = FALSE)
Y |
array of continuous outcomes (n x TT x r) |
X1 |
matrix of covariates affecting the initial probabilities (n x nc1) |
X2 |
array of covariates affecting the transition probabilities (n x TT-1 x nc2) |
yv |
vector of frequencies of the available configurations |
k |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
tol |
tolerance level for checking convergence of the algorithm |
maxit |
maximum number of iterations of the algorithm |
param |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
Mu |
initial value of the conditional means (r x k) (if start=2) |
Si |
initial value of the var-cov matrix common to all states (r x r) (if start=2) |
Be |
intial value of the parameters affecting the logit for the initial probabilities (if start=2) |
Ga |
intial value of the parametes affecting the logit for the transition probabilities (if start=2) |
output |
to return additional output (V,PI,Piv,Ul) |
out_se |
to compute the information matrix and standard errors |
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
Mu |
estimate of conditional means of the response variables |
Si |
estimate of var-cov matrix common to all states |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
lkv |
log-likelihood trace at every step |
Piv |
estimate of initial probability matrix |
PI |
estimate of transition probability matrices |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia, http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) TT <- 5 res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2, data_long_cont$Y3)) Y <- res$YY X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent_cont(Y, X1, X2, k = 3, output = TRUE) summary(est) # average transition probability matrix PI <- round(apply(est$PI[,,,2:TT], c(1,2), mean), 4) PI ## End(Not run)## Not run: # Example based on multivariate longitudinal continuous data data(data_long_cont) TT <- 5 res <- long2matrices(data_long_cont$id, X = cbind(data_long_cont$X1, data_long_cont$X2), Y = cbind(data_long_cont$Y1, data_long_cont$Y2, data_long_cont$Y3)) Y <- res$YY X1 <- res$XX[,1,] X2 <- res$XX[,2:TT,] # estimate the model est <- est_lm_cov_latent_cont(Y, X1, X2, k = 3, output = TRUE) summary(est) # average transition probability matrix PI <- round(apply(est$PI[,,,2:TT], c(1,2), mean), 4) PI ## End(Not run)
Main function for estimating LM model with covariates in the measurement model based on a global logit parameterization.
The function is no longer maintained. Please look at lmest function.
est_lm_cov_manifest(S, X, yv = rep(1,nrow(S)), k, q = NULL, mod = c("LM", "FM"), tol = 10^-8, maxit = 1000, start = 0, mu = NULL, al = NULL, be = NULL, si = NULL, rho = NULL, la = NULL, PI = NULL, output = FALSE, out_se = FALSE)est_lm_cov_manifest(S, X, yv = rep(1,nrow(S)), k, q = NULL, mod = c("LM", "FM"), tol = 10^-8, maxit = 1000, start = 0, mu = NULL, al = NULL, be = NULL, si = NULL, rho = NULL, la = NULL, PI = NULL, output = FALSE, out_se = FALSE)
S |
array of available configurations (n x TT) with categories starting from 0 |
X |
array (n x TT x nc) of covariates with eventually includes lagged response (nc = number of covariates) |
yv |
vector of frequencies of the available configurations |
k |
number of latent states |
q |
number of support points for the AR(1) process |
mod |
model ("LM" = Latent Markov with stationary transition, "FM" = finite mixture) |
tol |
tolerance for the convergence (optional) and tolerance of conditional probability if tol>1 then return |
maxit |
maximum number of iterations of the algorithm |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
mu |
starting value for mu (optional) |
al |
starting value for al (optional) |
be |
starting value for be (optional) |
si |
starting value for si when mod="FM" (optional) |
rho |
starting value for rho when mod="FM" (optional) |
la |
starting value for la (optional) |
PI |
starting value for PI (optional) |
output |
to return additional output (PRED0, PRED1) |
out_se |
TRUE for computing information matrix and standard errors |
mu |
vector of cutpoints |
al |
support points for the latent states |
be |
estimate of the vector of regression parameters |
si |
sigma of the AR(1) process (mod = "FM") |
rho |
parameter vector for AR(1) process (mod = "FM") |
la |
vector of initial probabilities |
PI |
transition matrix |
lk |
maximum log-likelihood |
np |
number of parameters |
aic |
value of AIC index |
bic |
value of BIC index |
PRED0 |
prediction of latent state |
PRED1 |
prediction of the overall latent effect |
sebe |
standard errors for the regression parameters be |
selrho |
standard errors for logit type transformation of rho |
J1 |
information matrix |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi - University of Perugia (IT)
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
Bartolucci, F., Bacci, S. and Pennoni, F. (2014) Longitudinal analysis of the self-reported health status by mixture latent autoregressive models, Journal of the Royal Statistical Society - series C, 63, pp. 267-288
## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) X <- res$XX S <- 5-res$YY # *** fit stationary LM model res0 <- vector("list", 10) tol <- 10^-6; for(k in 1:10){ res0[[k]] <- est_lm_cov_manifest(S, X, k, 1, mod = "LM", tol) save.image("example_SRHS.RData") } # *** fit the mixture latent auto-regressive model tol <- 0.005 res <- vector("list",4) k <- 1 q <- 51 res[[k]] <- est_lm_cov_manifest(S, X, k, q, mod = "FM", tol, output = TRUE) for(k in 2:4) res[[k]] <- est_lm_cov_manifest(S, X, k, q = 61, mod = "FM", tol, output = TRUE) ## End(Not run)## Not run: # Example based on self-rated health status (SRHS) data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long head(dataSRHS) res <- long2matrices(dataSRHS$id, X = cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4, dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100), Y = dataSRHS$srhs) X <- res$XX S <- 5-res$YY # *** fit stationary LM model res0 <- vector("list", 10) tol <- 10^-6; for(k in 1:10){ res0[[k]] <- est_lm_cov_manifest(S, X, k, 1, mod = "LM", tol) save.image("example_SRHS.RData") } # *** fit the mixture latent auto-regressive model tol <- 0.005 res <- vector("list",4) k <- 1 q <- 51 res[[k]] <- est_lm_cov_manifest(S, X, k, q, mod = "FM", tol, output = TRUE) for(k in 2:4) res[[k]] <- est_lm_cov_manifest(S, X, k, q = 61, mod = "FM", tol, output = TRUE) ## End(Not run)
Main function for estimating the mixed LM model with discrete random effect in the latent model.
The function is no longer maintained. Please look at lmestMixed function
est_lm_mixed(S, yv = rep(1,nrow(S)), k1, k2, start = 0, tol = 10^-8, maxit = 1000, out_se = FALSE)est_lm_mixed(S, yv = rep(1,nrow(S)), k1, k2, start = 0, tol = 10^-8, maxit = 1000, out_se = FALSE)
S |
array of available response configurations (n x TT x r) with categories starting from 0 |
yv |
vector of frequencies of the available configurations |
k1 |
number of latent classes |
k2 |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random) |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute standard errors |
la |
estimate of the mass probability vector (distribution of the random effects) |
Piv |
estimate of initial probabilities |
Pi |
estimate of transition probability matrices |
Psi |
estimate of conditional response probabilities |
lk |
maximum log-likelihood |
W |
posterior probabilities of the random effect |
np |
number of free parameters |
bic |
value of BIC for model selection |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi - University of Perugia (IT)
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based of criminal data # load data data(data_criminal_sim) out <- long2wide(data_criminal_sim, "id", "time", "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"), aggr = T, full = 999) XX <- out$XX YY <- out$YY freq <- out$freq n1 <- sum(freq[XX[,1] == 1]) n2 <- sum(freq[XX[,1] == 2]) n <- sum(freq) # fit mixed LM model only for females YY <- YY[XX[,1] == 2,,] freq <- freq[XX[,1] == 2] k1 <- 2 k2 <- 2 res <- est_lm_mixed(YY, freq, k1, k2, tol = 10^-8) summary(res) ## End(Not run)## Not run: # Example based of criminal data # load data data(data_criminal_sim) out <- long2wide(data_criminal_sim, "id", "time", "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"), aggr = T, full = 999) XX <- out$XX YY <- out$YY freq <- out$freq n1 <- sum(freq[XX[,1] == 1]) n2 <- sum(freq[XX[,1] == 2]) n <- sum(freq) # fit mixed LM model only for females YY <- YY[XX[,1] == 2,,] freq <- freq[XX[,1] == 2] k1 <- 2 k2 <- 2 res <- est_lm_mixed(YY, freq, k1, k2, tol = 10^-8) summary(res) ## End(Not run)
Main function for estimating the basic MC model.
The function is no longer maintained. Please look at lmestMc function.
est_mc_basic(S, yv, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE)est_mc_basic(S, yv, mod = 0, tol = 10^-8, maxit = 1000, out_se = FALSE)
S |
matrix (n x TT) of available configurations of the response variable with categories starting from 0 |
yv |
vector of frequencies of the available configurations |
mod |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors |
lk |
maximum log-likelihood |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
Fy |
estimated marginal distribution of the response variable for each time occasion |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
# Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] # fit of the Basic MC model out <- est_mc_basic(S, yv, mod = 1, out_se = TRUE) summary(out)# Example of drug consumption data # load data data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] # fit of the Basic MC model out <- est_mc_basic(S, yv, mod = 1, out_se = TRUE) summary(out)
Main function for estimating the MC model with covariates.
The function is no longer maintained. Please look at lmestMc function.
est_mc_cov(S, X1 = NULL, X2 = NULL, yv = rep(1,nrow(S)), start = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, output = FALSE, fort = TRUE)est_mc_cov(S, X1 = NULL, X2 = NULL, yv = rep(1,nrow(S)), start = 0, tol = 10^-8, maxit = 1000, out_se = FALSE, output = FALSE, fort = TRUE)
S |
matrix of available configurations of the response variable (n x TT) with categories starting from 0 |
X1 |
matrix of covariates affecting the initial probabilities (n x nc1) |
X2 |
array of covariates affecting the transition probabilities (n x TT-1 x nc2) |
yv |
vector of frequencies of the available configurations |
start |
type of starting values (0 = deterministic, 1 = random) |
tol |
tolerance level for checking convergence of the algorithm |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors |
output |
to return additional output (PI,Piv) |
fort |
to use fortran routine when possible (FALSE for not use fortran) |
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
np |
number of free parameters |
aic |
value of AIC for model selection |
bic |
value of BIC for model selection |
seBe |
standard errors for Be |
seGa |
standard errors for Ga |
Piv |
estimate of initial probability matrix |
PI |
estimate of transition probability matrices |
call |
command used to call the function |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia, http://www.stat.unipg.it/bartolucci
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based on criminal data # load criminal data data(data_criminal_sim) #We consider the response variable referring of crime of type 5 out <- long2wide(data_criminal_sim, "id", "time", "sex", "y5", aggr = T, full = 999) XX <- out$XX-1 YY <- out$YY freq <- out$freq TT <- 6 X1 <- as.matrix(XX[,1]) X2 <- as.matrix(XX[,2:TT]) # estimate the model res <- est_mc_cov(S = YY, yv = freq, X1 = X1, X2 = X2, output = TRUE) summary(res) # Initial probability for female Piv0 <- round(colMeans(res$Piv[X1 == 0,]), 4) # Initial probability for male Piv1 <- round(colMeans(res$Piv[X1 == 1,]), 4) ## End(Not run)## Not run: # Example based on criminal data # load criminal data data(data_criminal_sim) #We consider the response variable referring of crime of type 5 out <- long2wide(data_criminal_sim, "id", "time", "sex", "y5", aggr = T, full = 999) XX <- out$XX-1 YY <- out$YY freq <- out$freq TT <- 6 X1 <- as.matrix(XX[,1]) X2 <- as.matrix(XX[,2:TT]) # estimate the model res <- est_mc_cov(S = YY, yv = freq, X1 = X1, X2 = X2, output = TRUE) summary(res) # Initial probability for female Piv0 <- round(colMeans(res$Piv[X1 == 0,]), 4) # Initial probability for male Piv1 <- round(colMeans(res$Piv[X1 == 1,]), 4) ## End(Not run)
'LMbasic'
An S3 class object created by lmest function for basic Latent Markov (LM) model.
lk |
maximum log-likelihood at convergence of the EM algorithm |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices (k x k x TT) |
Psi |
estimate of conditional response probabilities (mb x k x r) |
np |
number of free parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion for model selection |
bic |
value of the Bayesian Information Criterion for model selection |
lkv |
log-likelihood trace at every step |
n |
sample size (sum of the weights when weights are provided) |
TT |
number of time occasions |
modBasic |
model on the transition probabilities: default 0 for time-heterogeneous transition matrices, 1 for time-homogeneous transition matrices, 2 for partial time homogeneity based on two transition matrices one from 2 to (TT-1) and the other for TT. |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
sePsi |
standard errors for the conditional response probabilities |
Lk |
vector containing the values of the log-likelihood of the LM model with each |
Bic |
vector containing the values of the BIC for each |
Aic |
vector containing the values of the AIC for each |
V |
array containing the estimated posterior probabilities of the latent states for each response configuration and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
S |
array containing the available response configurations |
yv |
vector of frequencies of the available configurations |
Pmarg |
matrix containing the marginal distribution of the latent states |
ns |
number of distinct response configurations |
call |
command used to call the function |
data |
data.frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
'LMbasiccont'
An S3 class object created by lmestCont function for the latent Markov (LM) model for continuous responses in long format.
lk |
maximum log-likelihood |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices (k x k x TT) |
Mu |
estimate of conditional means of the response variables (r x k) |
Si |
estimate of var-cov matrix common to all states (r x r) |
np |
number of free parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion for model selection |
bic |
value of the Bayesian Information Criterion for model selection |
lkv |
log-likelihood trace at every step |
n |
number of observations in the data |
TT |
number of time occasions |
modBasic |
model on the transition probabilities: default 0 for time-heterogeneous transition matrices, 1 for time-homogeneous transition matrices, 2 for partial time homogeneity based on two transition matrices one from 2 to (TT-1) and the other for TT |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
seMu |
standard errors for the conditional means |
seSi |
standard errors for the var-cov matrix |
sc |
score vector |
J |
information matrix |
Lk |
vector containing the values of the log-likelihood of the LM model with each |
Bic |
vector containing the values of the BIC of the LM model with each |
Aic |
vector containing the values of the AIC of the LM model with each |
V |
array containing the posterior distribution of the latent states for each units and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
Pmarg |
matrix containing the marginal distribution of the latent states |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Main function for estimating Latent Markov (LM) models for categorical responses.
lmest(responsesFormula = NULL, latentFormula = NULL, data, index, k = 1:4, start = 0, modSel = c("BIC", "AIC"), modBasic = 0, modManifest = c("LM", "FM"), paramLatent = c("multilogit", "difflogit"), weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, q = NULL, output = FALSE, parInit = list(piv = NULL, Pi = NULL, Psi = NULL, Be = NULL, Ga = NULL, mu = NULL, al = NULL, be = NULL, si = NULL, rho = NULL, la = NULL, PI = NULL, fixPsi = FALSE), fort = TRUE, seed = NULL, ntry = 0)lmest(responsesFormula = NULL, latentFormula = NULL, data, index, k = 1:4, start = 0, modSel = c("BIC", "AIC"), modBasic = 0, modManifest = c("LM", "FM"), paramLatent = c("multilogit", "difflogit"), weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, q = NULL, output = FALSE, parInit = list(piv = NULL, Pi = NULL, Psi = NULL, Be = NULL, Ga = NULL, mu = NULL, al = NULL, be = NULL, si = NULL, rho = NULL, la = NULL, PI = NULL, fixPsi = FALSE), fort = TRUE, seed = NULL, ntry = 0)
responsesFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section |
latentFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section |
data |
a |
index |
a character vector with two elements, the first indicating the name of the unit identifier, and the second the time occasions |
k |
an integer vector specifying the number of latent states (default: |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
modSel |
a string indicating the model selection criteria: "BIC" for Bayesian Information Criterion and "AIC" for Akaike Information Criterion Criterion |
modBasic |
model on the transition probabilities (0 for time-heterogeneity, 1 for time-homogeneity, from 2 to (TT-1) partial time-homogeneity of a certain order) |
modManifest |
model for manifest distribution when covariates are included in the measurement model ( |
paramLatent |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
weights |
an optional vector of weights for the available responses |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors |
q |
number of support points for the AR(1) process (if modManifest ="FM") |
output |
to return additional output: |
parInit |
list of initial model parameters when |
fort |
to use fortran routines when possible |
seed |
an integer value with the random number generator state |
ntry |
to set the number of random initializations |
lmest is a general function for estimating LM models for categorical responses. The function requires data in long format and two additional columns indicating the unit identifier and the time occasions.
Covariates are allowed to affect manifest distribution (measurement model) or the initial and transition probabilities (latent model). Two different formulas are employed to specify the different LM models, responsesFormula and latentFormula:
responsesFormula is used to specify the measurament model:
responsesFormula = y1 + y2 ~ NULL
the LM model without covariates and two responses (y1 and y2) is specified;
responsesFormula = NULL
all the columns in the data except the "id" and "time" columns are used as responses to estimate the LM model without covariates;
responsesFormula = y1 ~ x1 + x2
the univariate LM model with response (y1) and two covariates (x1 and x2) in the measurement model is specified;
latentFormula is used to specify the LM model with covariates in the latent model:
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ x1 + x2 | x3 + x4
the LM model with two responses (y1 and y2) and two covariates affecting the initial probabilities (x1 and x2) and other two affecting the transition probabilities (x3 and x4) is specified;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ 1 | x1 + x2
(or latentFormula = ~ NULL | x1 + x2)
the covariates affect only the transition probabilities and an intercept is specified for the intial probabilities;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ x1 + x2
the LM model with two covariates (x1 and x2) affecting both the initial and transition probabilities is specified;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ NULL | NULL
(or latentFormula = ~ 1 | 1)
the LM model with only an intercept on the initial and transition probabilities is specified.
The function also allows us to deal with missing responses, including drop-out and non-monotonic missingness, under the missing-at-random assumption. Missing values for the covariates are not allowed.
The LM model with individual covariates in the measurement model is estimated only for complete univariate responses. In such a case, two possible formulations are allowed: modManifest="LM" is used to estimate the model illustrated in Bartolucci et al. (2017), where the latent process is of first order with initial probabilities equal to those of the stationary distribution of the chain; modManifest="FM" is used to estimate a model relying on the assumption that the distribution of the latent process is a mixture of AR(1) processes with common variance and specific correlation coefficients. This model is illustrated in Bartolucci et al. (2014).
For continuous outcomes see the function lmestCont.
Returns an object of class 'LMbasic' for the model without covariates (see LMbasic-class), or an object of class 'LMmanifest' for the model with covariates on the manifest model (see LMmanifest-class), or an object of class 'LMlatent' for the model with covariates on the latent model (see LMlatent-class).
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Bartolucci, F., Bacci, S., and Pennoni, F. (2014). Longitudinal analysis of the self-reported health status by mixture latent autoregressive models, Journal of the Royal Statistical Society - series C, 63, pp. 267-288.
Bartolucci F., Pandolfi S., and Pennoni F. (2017) LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81(4), 1-38.
Bartolucci, F., Farcomeni, A., and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
### Basic LM model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, start = 1, modBasic = 1, seed = 123) out summary(out) ## Not run: ## Basic LM model with model selection using BIC out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:5, tol = 1e-8, modBasic = 1, seed = 123, ntry = 2) out1 out1$Bic # Basic LM model with model selection using AIC out2 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:5, tol = 1e-8, modBasic = 1, modSel = "AIC", seed = 123, ntry = 2) out2 out2$Aic # Criminal data data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) responsesFormula <- lmestFormula(data = data_criminal_sim,response = "y")$responsesFormula out3 <- lmest(responsesFormula = responsesFormula, index = c("id","time"), data =data_criminal_sim, k = 1:7, modBasic = 1, tol = 10^-4) out3 # Example of drug consumption data data("data_drug") long <- data_drug[,-6]-1 long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out4 <- lmest(index = c("id","time"), k = 3, data = long, weights = data_drug[,6], modBasic = 1) out4 summary(out4) ### LM model with covariates in the latent model # Covariates: gender, race, educational level (2 columns), age and age^2 out5 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) out5 summary(out5) ### LM model with the above covariates in the measurement model (stationary model) out6 <- lmest(responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, modManifest = "LM", out_se = TRUE, tol = 1e-8, start = 1, seed = 123) out6 summary(out6) #### LM model with covariates in the measurement model (mixture latent auto-regressive model) out7 <- lmest(responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, modManifest = "FM", q = 61, out_se = TRUE, tol = 1e-8) out7 summary(out7) ## End(Not run)### Basic LM model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, start = 1, modBasic = 1, seed = 123) out summary(out) ## Not run: ## Basic LM model with model selection using BIC out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:5, tol = 1e-8, modBasic = 1, seed = 123, ntry = 2) out1 out1$Bic # Basic LM model with model selection using AIC out2 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:5, tol = 1e-8, modBasic = 1, modSel = "AIC", seed = 123, ntry = 2) out2 out2$Aic # Criminal data data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) responsesFormula <- lmestFormula(data = data_criminal_sim,response = "y")$responsesFormula out3 <- lmest(responsesFormula = responsesFormula, index = c("id","time"), data =data_criminal_sim, k = 1:7, modBasic = 1, tol = 10^-4) out3 # Example of drug consumption data data("data_drug") long <- data_drug[,-6]-1 long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out4 <- lmest(index = c("id","time"), k = 3, data = long, weights = data_drug[,6], modBasic = 1) out4 summary(out4) ### LM model with covariates in the latent model # Covariates: gender, race, educational level (2 columns), age and age^2 out5 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) out5 summary(out5) ### LM model with the above covariates in the measurement model (stationary model) out6 <- lmest(responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, modManifest = "LM", out_se = TRUE, tol = 1e-8, start = 1, seed = 123) out6 summary(out6) #### LM model with covariates in the measurement model (mixture latent auto-regressive model) out7 <- lmest(responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, modManifest = "FM", q = 61, out_se = TRUE, tol = 1e-8) out7 summary(out7) ## End(Not run)
Main function for estimating Latent Markov (LM) models for continuous outcomes under the assumption of (multivariate) Gaussian distribution of the response variables given the latent process.
lmestCont(responsesFormula = NULL, latentFormula = NULL, data, index, k = 1:4, start = 0, modSel = c("BIC", "AIC"), modBasic = 0, paramLatent = c("multilogit", "difflogit"), weights = NULL, tol = 10^-10, maxit = 5000, out_se = FALSE, output = FALSE, parInit = list(piv = NULL, Pi = NULL, Mu = NULL, Si = NULL, Be = NULL, Ga = NULL), fort = TRUE, seed = NULL, ntry = 0, miss.imp = FALSE)lmestCont(responsesFormula = NULL, latentFormula = NULL, data, index, k = 1:4, start = 0, modSel = c("BIC", "AIC"), modBasic = 0, paramLatent = c("multilogit", "difflogit"), weights = NULL, tol = 10^-10, maxit = 5000, out_se = FALSE, output = FALSE, parInit = list(piv = NULL, Pi = NULL, Mu = NULL, Si = NULL, Be = NULL, Ga = NULL), fort = TRUE, seed = NULL, ntry = 0, miss.imp = FALSE)
responsesFormula |
a symbolic description of the model to be fitted. A detailed description is given in the ‘Details’ section |
latentFormula |
a symbolic description of the model to be fitted. A detailed description is given in the ‘Details’ section |
data |
a |
index |
a character vector with two elements, the first indicating the name of the unit identifier, and the second the time occasions |
k |
an integer vector specifying the number of latent states (default: |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
modSel |
a string indicating the model selection criteria: "BIC" for Bayesian Information Criterion and "AIC" for Akaike Information Criterion Criterion |
modBasic |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
paramLatent |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
weights |
vector of weights |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors (By default is set to FALSE) |
output |
to return additional output ( |
parInit |
list of initial model parameters when |
fort |
to use fortran routines when possible (By default is set to TRUE) |
seed |
an integer value with the random number generator state |
ntry |
to set the number of random initializations |
miss.imp |
how to deal with missing values (TRUE for imputation through the imp.mix function, FALSE for missing at random assumption) |
The function lmestCont is a general function for estimating LM models for continuous responses. The function requires data in long format and two additional columns indicating the unit identifier and the time occasions.
Covariates are allowed on the initial and transition probabilities (latent model). Two different formulas are employed to specify the different LM models, responsesFormula and latentFormula:
responsesFormula is used to specify the measurament model:
responsesFormula = y1 + y2 ~ NULL
the LM model without covariates and two responses (y1 and y2) is specified.
responsesFormula = NULL
all the columns in the data except the "id" and "time" columns are used as responses to estimate the LM model without covariates;
responsesFormula = y1 + y2 ~ x1 + x2
the LM model with two responses (y1 and y2) and two covariates in the measurement model is specified;
latentFormula is used to specify the LM model with covariates in the latent model:
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ x1 + x2 | x3 + x4
the LM model with two responses (y1 and y2) and two covariates affecting the initial probabilities (x1 and x2) and other two affecting the transition probabilities (x3 and x4) is specified;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ 1 | x1 + x2
(or latentFormula = ~ NULL | x1 + x2)
the covariates affect only the transition probabilities and an intercept is specified for the intial probabilities;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ x1 + x2
the LM model with two covariates (x1 and x2) affecting both the initial and transition probabilities is specified;
responsesFormula = y1 + y2 ~ NULL latentFormula = ~ NULL | NULL
(or latentFormula = ~ 1 | 1)
the LM model with only an intercept on the initial and transition probabilities is specified.
The function also allows us to deal with missing responses using the mix package (Schafer, 2024) for imputing the missing values. Missing values for the covariates are not allowed.
For categorical outcomes see the function lmest.
Returns an object of class 'LMbasiccont' for the model without covariates (see LMbasiccont-class), an object of class 'LMlatentcont' for the model with covariates on the latent model (see LMlatentcont-class), or an object of class 'LMmanifestcont' for the model with covariates on the measurement model (see LMmanifestcont-class)).
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni
Bartolucci F., Pandolfi S., Pennoni F. (2017) LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81(4), 1-38.
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: data(data_long_cont) # Basic LM model out <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 3, modBasic = 1, tol = 10^-5) out summary(out) # Basic LM model with model selection using BIC out1 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, ntry = 2, modBasic = 1, tol = 10^-5) out1 out1$Bic # Basic LM model with model selection using AIC out2 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, modBasic = 1, ntry = 2, modSel = "AIC", tol = 10^-5) out2 out2$Aic # LM model with covariates in the measurement model out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out3 summary(out3) # LM model with covariates in the latent model out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out4 summary(out4) # LM model with two covariates affecting the initial probabilities and one # affecting the transition probabilities out5 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2 | X1, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out5 summary(out5) ## End(Not run)## Not run: data(data_long_cont) # Basic LM model out <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 3, modBasic = 1, tol = 10^-5) out summary(out) # Basic LM model with model selection using BIC out1 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, ntry = 2, modBasic = 1, tol = 10^-5) out1 out1$Bic # Basic LM model with model selection using AIC out2 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, modBasic = 1, ntry = 2, modSel = "AIC", tol = 10^-5) out2 out2$Aic # LM model with covariates in the measurement model out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out3 summary(out3) # LM model with covariates in the latent model out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out4 summary(out4) # LM model with two covariates affecting the initial probabilities and one # affecting the transition probabilities out5 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2 | X1, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out5 summary(out5) ## End(Not run)
LMest functionsAn object of class lmestData containing data in long format, some necessary information on the data structure and objects for the estimation functions.
lmestData(data, id = NULL, time = NULL, idAsFactor = TRUE, timeAsFactor = TRUE, responsesFormula = NULL, latentFormula = NULL, na.rm = FALSE, check.names = FALSE)lmestData(data, id = NULL, time = NULL, idAsFactor = TRUE, timeAsFactor = TRUE, responsesFormula = NULL, latentFormula = NULL, na.rm = FALSE, check.names = FALSE)
data |
a matrix or data frame in long format of observation |
id |
a numeric vector or a string indicating the column with the unit identifier. If NULL, the first column is considered |
time |
a numeric vector or a string indicating the column with the time occasions. If NULL, the second column is considered, and if the |
idAsFactor |
a logical value indicating whether or not the column with the ids is converted to a factor. (By default is set to TRUE) |
timeAsFactor |
a logical value indicating whether or not the column with the time occasions is converted in a factor. (By default is set to TRUE) |
responsesFormula |
|
latentFormula |
|
na.rm |
a logical value indicating whether or not the observation with at least a missing value is removed (By default is set to FALSE) |
check.names |
a logical value indicating whether or not the names of the variables are syntactically valid, and adjusted if necessary. (By default is set to FALSE) |
An object of class 'lmestData' with the following objects:
data |
a data.frame object to use in the estimation functions |
id |
a integer vector with the unit identifier |
time |
a integer vector with the time occasions |
n |
the number of observation |
TT |
an integer value indicating number of time occasions |
d |
an interger value indicating the number of variables (columns except id and time) |
Y |
the response variables |
Xmanifest |
the variables affecting the measurement model if specified in |
Xinitial |
the variables affecting the initial probabilities of the latent model if specified in |
Xtrans |
the variables affecting the transition probabilities of the latent model if specified in |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
data(data_long_cont) str(data_long_cont) ## Data with continous resposes dt <- lmestData(data = data_long_cont, id = "id",time="time") str(dt) ## Summary of each variable and for each time summary(dt) ## Summary of each variable summary(dt, type = "cross") ## Summary of each variable by time summary(dt, type = "year") plot(dt) plot(dt, typePlot = "sh") ####################### ## Not run: data("data_criminal_sim") dt1 <- lmestData(data = data_criminal_sim, id = "id", time = "time") str(dt1) summary(dt1, varType = rep("d",ncol(dt1$Y))) dt2 <- lmestData(data = data_criminal_sim, id = "id", time = "time", responsesFormula = y1 + y2 ~ y3, latentFormula = ~ y7 + y8 | y9 + y10) str(dt2) ## Summary for responses, covariates on the manifest distribution, ## covariates on intial and transition probabilities summary(dt2, dataSummary = "responses",varType = rep("d",ncol(dt2$Y))) summary(dt2, dataSummary = "manifest",varType = rep("d",ncol(dt2$Xmanifest))) summary(dt2, dataSummary = "initial",varType = rep("d",ncol(dt2$Xinitial))) summary(dt2, dataSummary = "transition",varType = rep("d",ncol(dt2$Xtrans))) ## End(Not run)data(data_long_cont) str(data_long_cont) ## Data with continous resposes dt <- lmestData(data = data_long_cont, id = "id",time="time") str(dt) ## Summary of each variable and for each time summary(dt) ## Summary of each variable summary(dt, type = "cross") ## Summary of each variable by time summary(dt, type = "year") plot(dt) plot(dt, typePlot = "sh") ####################### ## Not run: data("data_criminal_sim") dt1 <- lmestData(data = data_criminal_sim, id = "id", time = "time") str(dt1) summary(dt1, varType = rep("d",ncol(dt1$Y))) dt2 <- lmestData(data = data_criminal_sim, id = "id", time = "time", responsesFormula = y1 + y2 ~ y3, latentFormula = ~ y7 + y8 | y9 + y10) str(dt2) ## Summary for responses, covariates on the manifest distribution, ## covariates on intial and transition probabilities summary(dt2, dataSummary = "responses",varType = rep("d",ncol(dt2$Y))) summary(dt2, dataSummary = "manifest",varType = rep("d",ncol(dt2$Xmanifest))) summary(dt2, dataSummary = "initial",varType = rep("d",ncol(dt2$Xinitial))) summary(dt2, dataSummary = "transition",varType = rep("d",ncol(dt2$Xtrans))) ## End(Not run)
Function that performs local and global decoding (Viterbi algorithm) from the output of lmest, lmestCont, and lmestMixed.
lmestDecoding(est, sequence = NULL, fort = TRUE, ...) ## S3 method for class 'LMbasic' lmestDecoding(est, sequence = NULL,fort = TRUE, ...) ## S3 method for class 'LMmanifest' lmestDecoding(est, sequence = NULL, fort = TRUE, ...) ## S3 method for class 'LMlatent' lmestDecoding(est, sequence = NULL, fort = TRUE,...) ## S3 method for class 'LMbasiccont' lmestDecoding(est, sequence = NULL, fort = TRUE,...) ## S3 method for class 'LMmixed' lmestDecoding(est, sequence = NULL, fort = TRUE,...)lmestDecoding(est, sequence = NULL, fort = TRUE, ...) ## S3 method for class 'LMbasic' lmestDecoding(est, sequence = NULL,fort = TRUE, ...) ## S3 method for class 'LMmanifest' lmestDecoding(est, sequence = NULL, fort = TRUE, ...) ## S3 method for class 'LMlatent' lmestDecoding(est, sequence = NULL, fort = TRUE,...) ## S3 method for class 'LMbasiccont' lmestDecoding(est, sequence = NULL, fort = TRUE,...) ## S3 method for class 'LMmixed' lmestDecoding(est, sequence = NULL, fort = TRUE,...)
est |
an object obtained from a call to |
sequence |
an integer vector indicating the units for the decoding. If |
fort |
to use fortran routines when possible |
... |
further arguments |
Ul |
matrix of local decoded states corresponding to each row of Y |
Ug |
matrix of global decoded states corresponding to each row of Y |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Viterbi A. (1967) Error Bounds for Convolutional Codes and an Asymptotically Optimum Decoding Algorithm. IEEE Transactions on Information Theory, 13, 260-269.
Juan B., Rabiner L. (1991) Hidden Markov Models for Speech Recognition. Technometrics, 33, 251-272.
# Decoding for basic LM model data("data_drug") long <- data_drug[,-6]-1 long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) est <- lmest(index = c("id","time"), k = 3, data = long, weights = data_drug[,6], modBasic = 1) # Decoding for a single sequence out1 <- lmestDecoding(est, sequence = 1) out2 <- lmestDecoding(est, sequence = 1:4) # Decoding for all sequences out3 <- lmestDecoding(est) ## Not run: # Decoding for LM model with covariates on the initial and transition probabilities data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs est2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "difflogit", output = TRUE) # Decoding for a single sequence out3 <- lmestDecoding(est2, sequence = 1) # Decoding for the first three sequences out4 <- lmestDecoding(est2, sequence = 1:3) # Decoding for all sequences out5 <- lmestDecoding(est2) ## End(Not run)# Decoding for basic LM model data("data_drug") long <- data_drug[,-6]-1 long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) est <- lmest(index = c("id","time"), k = 3, data = long, weights = data_drug[,6], modBasic = 1) # Decoding for a single sequence out1 <- lmestDecoding(est, sequence = 1) out2 <- lmestDecoding(est, sequence = 1:4) # Decoding for all sequences out3 <- lmestDecoding(est) ## Not run: # Decoding for LM model with covariates on the initial and transition probabilities data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs est2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "difflogit", output = TRUE) # Decoding for a single sequence out3 <- lmestDecoding(est2, sequence = 1) # Decoding for the first three sequences out4 <- lmestDecoding(est2, sequence = 1:3) # Decoding for all sequences out5 <- lmestDecoding(est2) ## End(Not run)
LMest functionsBulding formulas for lmest, lmestCont, lmestMixed, and lmestMc.
lmestFormula(data, response, manifest = NULL, LatentInitial = NULL, LatentTransition = NULL, AddInterceptManifest = FALSE, AddInterceptInitial = TRUE, AddInterceptTransition = TRUE, responseStart = TRUE, manifestStart = TRUE, LatentInitialStart = TRUE, LatentTransitionStart = TRUE)lmestFormula(data, response, manifest = NULL, LatentInitial = NULL, LatentTransition = NULL, AddInterceptManifest = FALSE, AddInterceptInitial = TRUE, AddInterceptTransition = TRUE, responseStart = TRUE, manifestStart = TRUE, LatentInitialStart = TRUE, LatentTransitionStart = TRUE)
data |
a data.frame or a matrix of data |
response |
a numeric or character vector indicating the column indices or the names for the response variables |
manifest |
a numeric or character vector indicating the column indices or the names for the covariates affecting the measurement model |
LatentInitial |
a numeric or character vector indicating the column indices or the names for the covariates affecting the initial probabilities |
LatentTransition |
a numeric or character vector indicating the column indices or the names for the covariates affecting the transition probabilities |
AddInterceptManifest |
a logical value indicating whether the intercept is added to the covariates affecting the measurement model |
AddInterceptInitial |
a logical value indicating whether the intercept is added to covariates affecting the initial probabilities |
AddInterceptTransition |
a logical value indicating whether the intercept is added to covariates affecting the transition probabilities |
responseStart |
a logical value indicating whether the response variables names start with |
manifestStart |
a logical value indicating whether the covariates names start with |
LatentInitialStart |
a logical value indicating whether the covariates names start with |
LatentTransitionStart |
a logical value indicating whether the covariates names start with |
Generates formulas for responsesFormula and latentFormula to use in lmest, lmestCont, lmestMixed, and lmestMc.
Returns a list with responsesFormula and latentFormula objects.
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
data(data_SRHS_long) names(data_SRHS_long) # Formula with response srhs and covariates for both initail and transition: # gender,race,educational,age. ## LM model with covariates on the latent model # and with intercepts on the initial and transition probabilities fm <- lmestFormula(data = data_SRHS_long, response = "srhs", LatentInitial = 3:6, LatentTransition = 3:6) fm ## LM model with covariates on the latent model # and without intercepts on the initial and transition probabilities fm <- lmestFormula(data = data_SRHS_long, response = "srhs", LatentInitial = 3:6, LatentTransition = 3:6, AddInterceptInitial = FALSE,AddInterceptTransition = FALSE) fm ###### data(data_criminal_sim) str(data_criminal_sim) # Formula with only the responses from y1 to y10 fm <- lmestFormula(data = data_criminal_sim,response = "y")$responsesFormula fm # Formula with only the responses from y1 to y10 and intercept for manifest fm <- lmestFormula(data = data_criminal_sim, response = "y",AddInterceptManifest = TRUE)$responsesFormula fm ## LM model for continous responses data(data_long_cont) names(data_long_cont) # Formula with response Y1, Y2, no covariate for manifest, # X1 covariates for initail and X2 covariate for transition fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = "X", LatentTransition = "X2") fm ## Wrong model specification since two variable start with X. # Check the starts arguments. # For the right model: fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = "X1",LatentTransition = "X2") fm ## or fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = 6,LatentTransition = "X2", LatentInitialStart = FALSE) fm ## Not run: data(data_criminal_sim) data_criminal_sim <- data.frame(data_criminal_sim) # Mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula out <- lmest(responsesFormula = responsesFormula, index = c("id","time"), data = data_criminal_sim, k = 2) ## End(Not run)data(data_SRHS_long) names(data_SRHS_long) # Formula with response srhs and covariates for both initail and transition: # gender,race,educational,age. ## LM model with covariates on the latent model # and with intercepts on the initial and transition probabilities fm <- lmestFormula(data = data_SRHS_long, response = "srhs", LatentInitial = 3:6, LatentTransition = 3:6) fm ## LM model with covariates on the latent model # and without intercepts on the initial and transition probabilities fm <- lmestFormula(data = data_SRHS_long, response = "srhs", LatentInitial = 3:6, LatentTransition = 3:6, AddInterceptInitial = FALSE,AddInterceptTransition = FALSE) fm ###### data(data_criminal_sim) str(data_criminal_sim) # Formula with only the responses from y1 to y10 fm <- lmestFormula(data = data_criminal_sim,response = "y")$responsesFormula fm # Formula with only the responses from y1 to y10 and intercept for manifest fm <- lmestFormula(data = data_criminal_sim, response = "y",AddInterceptManifest = TRUE)$responsesFormula fm ## LM model for continous responses data(data_long_cont) names(data_long_cont) # Formula with response Y1, Y2, no covariate for manifest, # X1 covariates for initail and X2 covariate for transition fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = "X", LatentTransition = "X2") fm ## Wrong model specification since two variable start with X. # Check the starts arguments. # For the right model: fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = "X1",LatentTransition = "X2") fm ## or fm <- lmestFormula(data = data_long_cont, response = c("Y"), LatentInitial = 6,LatentTransition = "X2", LatentInitialStart = FALSE) fm ## Not run: data(data_criminal_sim) data_criminal_sim <- data.frame(data_criminal_sim) # Mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula out <- lmest(responsesFormula = responsesFormula, index = c("id","time"), data = data_criminal_sim, k = 2) ## End(Not run)
Main function for estimating Markov Chain (MC) models for categorical responses with or without covariates.
lmestMc(responsesFormula = NULL, data, index, start = 0, modBasic = 0, weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, output = FALSE, fort = TRUE, seed = NULL)lmestMc(responsesFormula = NULL, data, index, start = 0, modBasic = 0, weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, output = FALSE, fort = TRUE, seed = NULL)
responsesFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section |
data |
a |
index |
a character vector with two elements, the first indicating the name of the unit identifier, and the second the time occasions |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
modBasic |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
weights |
an optional vector of weights for the available responses |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors (FALSE is the default option) |
output |
to return additional output ( |
fort |
to use fortran routines when possible (By default is set to TRUE) |
seed |
An integer value with the random number generator state. |
The function lmestMc estimates the basic MC model and the MC model with covariates for categorical responses. The function requires data in long format and two additional column indicating the unit identifier and the time occasions.
responsesFormula is used to specify the basic MC models and the model with covariates:
responsesFormula = y1 + y2 ~ NULL
the MC model without covariates and two responses (y1 and y2) is specified;
responsesFormula = NULL
all the columns in the data except the "id" and "time" columns are used to estimate MC without covariates;
responsesFormula = y1 ~ x1 + x2 | x3 + x4
the MC model with one response (y1), two covariates affecting the initial probabilities (x1 and x2) and other two different covariates affecting the transition probabilities (x3 and x4) is specified;
responsesFormula = y1 ~ x1 + x2
the MC model with one response (y1) and two covariates (x1 and x2) affecting both the initial and transition probabilities is specified.
Missing responses are not allowed.
Returns an object of class 'MCbasic' for the basic model without covariates (see MCbasic-class), or an object of class 'MCcov' for the model with covariates (see MCcov-class).
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Bartolucci F., Pandolfi S., Pennoni F. (2017) LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81(4), 1-38.
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Basic Markov Chain model data("RLMSlong") # Categories rescaled from 1 “absolutely unsatisfied” to 5 “absolutely satisfied” RLMSlong$value <- 5 - RLMSlong$value out <- lmestMc(responsesFormula = value ~ NULL, index = c("id","time"), modBasic = 1, data = RLMSlong) out summary(out) # Example of drug consumption data data("data_drug") long <- data_drug[,-6] long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out1 <- lmestMc(index = c("id","time"), data = long, weights = data_drug[,6], modBasic = 1, out_se = TRUE) out1 ### MC model with covariates ### Covariates: gender, race, educational level (2 columns), age and age^2 data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories of the responses rescaled from 1 “poor” to 5 “excellent” SRHS$srhs <- 5 - SRHS$srhs out2 <- lmestMc(responsesFormula = srhs ~ I( 0 + (race==2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS) out2 summary(out2) # Criminal data data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) out3 <- lmestMc(responsesFormula = y5~sex, index = c("id","time"), data = data_criminal_sim, output = TRUE) out3 ## End(Not run)## Not run: # Basic Markov Chain model data("RLMSlong") # Categories rescaled from 1 “absolutely unsatisfied” to 5 “absolutely satisfied” RLMSlong$value <- 5 - RLMSlong$value out <- lmestMc(responsesFormula = value ~ NULL, index = c("id","time"), modBasic = 1, data = RLMSlong) out summary(out) # Example of drug consumption data data("data_drug") long <- data_drug[,-6] long <- data.frame(id = 1:nrow(long),long) long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out1 <- lmestMc(index = c("id","time"), data = long, weights = data_drug[,6], modBasic = 1, out_se = TRUE) out1 ### MC model with covariates ### Covariates: gender, race, educational level (2 columns), age and age^2 data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories of the responses rescaled from 1 “poor” to 5 “excellent” SRHS$srhs <- 5 - SRHS$srhs out2 <- lmestMc(responsesFormula = srhs ~ I( 0 + (race==2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS) out2 summary(out2) # Criminal data data(data_criminal_sim) data_criminal_sim = data.frame(data_criminal_sim) out3 <- lmestMc(responsesFormula = y5~sex, index = c("id","time"), data = data_criminal_sim, output = TRUE) out3 ## End(Not run)
Main function for estimating the mixed latent Markov (LM) models for categorical responses with discrete random effects in the latent model.
lmestMixed(responsesFormula = NULL, data, index, k1, k2, start = 0, weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, seed = NULL)lmestMixed(responsesFormula = NULL, data, index, k1, k2, start = 0, weights = NULL, tol = 10^-8, maxit = 1000, out_se = FALSE, seed = NULL)
responsesFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section |
data |
a |
index |
a character vector with two elements, the first indicating the name of the unit identifier, and the second the time occasions |
k1 |
number of latent classes |
k2 |
number of latent states |
start |
type of starting values (0 = deterministic, 1 = random, 2 = initial values in input) |
weights |
an optional vector of weights for the available responses |
tol |
tolerance level for convergence |
maxit |
maximum number of iterations of the algorithm |
out_se |
to compute the information matrix and standard errors (FALSE is the default option) |
seed |
an integer value with the random number generator state |
The function lmestMixed estimates the mixed LM for categorical data. The function requires data in long format and two additional columns indicating the unit identifier and the time occasions.
responsesFormula is used to specify the responses of the mixed LM model:
responsesFormula = y1 + y2 ~ NULL
the mixed LM model with two categorical responses (y1 and y2) is specified;
responsesFormula = NULL
all the columns in the data except the "id" and "time" columns are used as responses to estimate the mixed LM.
Missing responses are not allowed.
Returns an object of class 'LMmixed' (see LMmixed-class).
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Bartolucci F., Pandolfi S., Pennoni F. (2017) LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81(4), 1-38.
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
## Not run: # Example based on criminal data data(data_criminal_sim) data_criminal_sim <- data.frame(data_criminal_sim) # Estimate mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula # fit mixed LM model only for females out <- lmestMixed(responsesFormula = responsesFormula, index = c("id","time"), k1 = 2, k2 = 2, data = data_criminal_sim[data_criminal_sim$sex == 2,]) out summary(out) ## End(Not run)## Not run: # Example based on criminal data data(data_criminal_sim) data_criminal_sim <- data.frame(data_criminal_sim) # Estimate mixed LM model for females responsesFormula <- lmestFormula(data = data_criminal_sim, response = "y")$responsesFormula # fit mixed LM model only for females out <- lmestMixed(responsesFormula = responsesFormula, index = c("id","time"), k1 = 2, k2 = 2, data = data_criminal_sim[data_criminal_sim$sex == 2,]) out summary(out) ## End(Not run)
Function that searches for the global maximum of the log-likelihood of different models and selects the optimal number of states.
lmestSearch(responsesFormula = NULL, latentFormula = NULL, data, index, k, version = c("categorical", "continuous"), weights = NULL, nrep = 2, tol1 = 10^-5, tol2 = 10^-10, out_se = FALSE, miss.imp = FALSE, seed = NULL, ...)lmestSearch(responsesFormula = NULL, latentFormula = NULL, data, index, k, version = c("categorical", "continuous"), weights = NULL, nrep = 2, tol1 = 10^-5, tol2 = 10^-10, out_se = FALSE, miss.imp = FALSE, seed = NULL, ...)
responsesFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section of |
latentFormula |
a symbolic description of the model to fit. A detailed description is given in the ‘Details’ section of |
data |
a |
index |
a character vector with two elements, the first indicating the name of the unit identifier, and the second the time occasions |
k |
a vector of integer values for the number of latent states |
weights |
an optional vector of weights for the available responses |
version |
type of responses for the LM model: "categorical" and "continuous" |
nrep |
number of repetitions of each random initialization |
tol1 |
tolerance level for checking convergence of the algorithm in the random initializations |
tol2 |
tolerance level for checking convergence of the algorithm in the last deterministic initialization |
out_se |
to compute the information matrix and standard errors (FALSE is the default option) |
miss.imp |
Only for continuous responses: how to deal with missing values (TRUE for imputation through the imp.mix function, FALSE for missing at random assumption) |
seed |
an integer value with the random number generator |
... |
additional arguments to be passed to functions |
The function combines deterministic and random initializations strategy to reach the global maximum of the model log-likelihood.
It uses one deterministic initialization (start=0) and a number of random initializations (start=1) proportional to the number of latent states. The tolerance level is set equal to 10^-5. Starting from the best solution obtained in this way, a final run is performed (start=2) with a default tolerance level equal to 10^-10.
Missing responses are allowed according to the model to be estimated.
Returns an object of class 'LMsearch' with the following components:
out.single |
Output of every LM model estimated for each number of latent states given in input |
Aic |
Values the Akaike Information Criterion for each number of latent states given in input |
Bic |
Values of the Bayesian Information Criterion for each number of latent states given in input |
lkv |
Values of log-likelihood for each number of latent states given in input. |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Bartolucci F., Pandolfi S., Pennoni F. (2017) LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data, Journal of Statistical Software, 81(4), 1-38.
Bartolucci, F., Farcomeni, A. and Pennoni, F. (2013) Latent Markov Models for Longitudinal Data, Chapman and Hall/CRC press.
### Example with data on drug use in wide format data("data_drug") long <- data_drug[,-6] # add labels referred to the identifier long <- data.frame(id = 1:nrow(long),long) # reshape data from the wide to the long format long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out <- lmestSearch(data = long, index = c("id","time"), version = "categorical", k = 1:3, weights = data_drug[,6], modBasic = 1, seed = 123) out summary(out$out.single[[3]]) ## Not run: ### Example with data on self rated health # LM model with covariates in the measurement model data("data_SRHS_long") SRHS <- data_SRHS_long[1:1000,] # Categories rescaled to vary from 1 (“poor”) to 5 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out1 <- lmestSearch(data = SRHS, index = c("id","t"), version = "categorical", responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), k = 1:2, out_se = TRUE, seed = 123) summary(out1) summary(out1$out.single[[2]]) ## End(Not run)### Example with data on drug use in wide format data("data_drug") long <- data_drug[,-6] # add labels referred to the identifier long <- data.frame(id = 1:nrow(long),long) # reshape data from the wide to the long format long <- reshape(long,direction = "long", idvar = "id", varying = list(2:ncol(long))) out <- lmestSearch(data = long, index = c("id","time"), version = "categorical", k = 1:3, weights = data_drug[,6], modBasic = 1, seed = 123) out summary(out$out.single[[3]]) ## Not run: ### Example with data on self rated health # LM model with covariates in the measurement model data("data_SRHS_long") SRHS <- data_SRHS_long[1:1000,] # Categories rescaled to vary from 1 (“poor”) to 5 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out1 <- lmestSearch(data = SRHS, index = c("id","t"), version = "categorical", responsesFormula = srhs ~ -1 + I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), k = 1:2, out_se = TRUE, seed = 123) summary(out1) summary(out1$out.single[[2]]) ## End(Not run)
'LMlatent'
An S3 class object created by lmest for Latent Markov (LM) model with covariates in the latent model.
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
Piv |
estimate of initial probability matrix. The first state is used as reference category when |
PI |
estimate of transition probability matrices. State u is used as reference category when |
Psi |
estimate of conditional response probabilities (mb x k x r) |
np |
number of free parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion for model selection |
bic |
value of the Bayesian Information Criterion for model selection |
lkv |
log-likelihood trace at every step of the EM algorithm |
n |
number of observations in the data |
TT |
number of time occasions |
paramLatent |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
sePsi |
standard errors for the conditional response matrix |
seBe |
standard errors for |
seGa |
standard errors for |
Lk |
vector containing the values of the log-likelihood of the LM model with each |
Bic |
vector containing the values of the BIC for each |
Aic |
vector containing the values of the AIC for each |
V |
array containing the posterior distribution of the latent states for each response configuration and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
S |
array containing the available response configurations |
yv |
vector of frequencies of the available configurations |
Pmarg |
matrix containing the marginal distribution of the latent states |
call |
command used to call the function |
data |
Data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
'LMlatentcont'
An S3 class object created by lmestCont for the Latent Markov (LM) model for continuous responses in long format with covariates in the latent model.
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
Mu |
estimate of conditional means of the response variables |
Si |
estimate of var-cov matrix common to all states |
np |
number of free parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion for model selection |
bic |
value of the Bayesian Information Criterion for model selection |
lkv |
log-likelihood trace at every step |
n |
number of observations in the data |
TT |
number of time occasions |
paramLatent |
type of parametrization for the transition probabilities ("multilogit" = standard multinomial logit for every row of the transition matrix, "difflogit" = multinomial logit based on the difference between two sets of parameters) |
seMu |
standard errors for the conditional means |
seSi |
standard errors for the var-cov matrix |
seBe |
standard errors for |
seGa |
standard errors for Ga |
sc |
score vector |
J |
information matrix |
PI |
estimate of transition probability matrices |
Piv |
estimate of initial probability matrix |
Lk |
vector containing the values of the log-likelihood of the LM model with each |
Bic |
vector containing the values of the BIC of the LM model with each |
Aic |
vector containing the values of the AIC of the LM model with each |
V |
array containing the posterior distribution of the latent states for each units and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
Pmarg |
matrix containing the marginal distribution of the latent states |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
'LMmanifest'
An S3 class object created by lmest for Latent Markov (LM) model with covariates in the measurement model.
mu |
vector of cut-points |
al |
support points for the latent states |
be |
estimate of the vector of regression parameters |
si |
sigma of the AR(1) process (mod = "FM") |
rho |
parameter vector for AR(1) process (mod = "FM") |
la |
vector of initial probabilities |
PI |
transition matrix |
lk |
maximum log-likelihood |
np |
number of parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion |
bic |
value of Bayesian Information Criterion |
n |
number of observations in the data |
TT |
number of time occasions |
modManifest |
for LM model with covariates on the manifest model: "LM" = Latent Markov with stationary transition, "FM" = finite mixture model where a mixture of AR(1) processes is estimated with common variance and specific correlation coefficients |
sebe |
standard errors for the regression parameters be |
selrho |
standard errors for logit type transformation of rho |
J1 |
information matrix |
V |
array containing the posterior distribution of the latent states for each units and time occasion |
PRED1 |
prediction of the overall latent effect |
S |
array containing the available response configurations |
yv |
vector of frequencies of the available configurations |
Pmarg |
matrix containing the marginal distribution of the latent states |
Lk |
vector containing the values of the log-likelihood of the LM model with each |
Bic |
vector containing the values of the BIC for each |
Aic |
vector containing the values of the AIC for each |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
'LMmanifestcont'
An S3 class object created by lmestCont for Latent Markov (LM) model for continuous responses in long format with covariates in the measurement model.
Al |
support points for the latent states |
Be |
estimate of the vector of regression parameters |
Si |
estimate of var-cov matrix common to all states |
piv |
vector of initial probabilities |
Pi |
transition matrix |
lk |
maximum log-likelihood |
np |
number of parameters |
k |
optimal number of latent states |
aic |
value of the Akaike Information Criterion |
bic |
value of Bayesian Information Criterion |
n |
number of observations in the data |
TT |
number of time occasions |
modBasic |
model on the transition probabilities (0 for time-heter., 1 for time-homog., from 2 to (TT-1) partial homog. of that order) |
lkv |
log-likelihood trace at every step |
seAl |
standard errors for the support points Al |
seBe |
standard errors regression parameters Be |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
seSi |
standard errors for the var-cov matrix |
Lk |
vector containing the values of the log-likelihood of the LM model for each |
Np |
vector containing the number of parameters for each |
Bic |
vector containing the values of the BIC for each |
Aic |
vector containing the values of the AIC for each |
J |
information matrix |
sc |
score vector |
V |
array containing the posterior distribution of the latent states for each units and time occasion |
Ul |
matrix containing the predicted sequence of latent states by the local decoding method |
Pmarg |
matrix containing the marginal distribution of the latent states |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni
'LMmixed'
An S3 class object created by lmestMixed for the mixed latent Markov (LM) models for categorical data in long format.
la |
estimate of the mass probability vector (distribution of the random effects) |
Piv |
estimate of initial probabilities |
Pi |
estimate of transition probability matrices |
Psi |
estimate of conditional response probabilities |
lk |
maximum log-likelihood |
W |
posterior probabilities of the random effect |
np |
number of free parameters |
k1 |
number of support points (latent classes) of the latent variable defining the unobserved clusters |
k2 |
number of support points (latent states) of the latent variable defining the first-order Markov process |
bic |
value of the Akaike Information Criterion for model selection |
aic |
value of the Akaike Information Criterion for model selection |
n |
number of observations in the data |
TT |
number of time occasions |
sela |
standard errors for |
sePiv |
estimate of initial probability matrix |
sePi |
standard errors for the transition probabilities |
sePsi |
standard errors for the conditional response matrix |
call |
command used to call the function |
data |
the input data |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Function that transforms data in the long format to data in array format.
long2matrices(id, time = NULL, X = NULL, Y)long2matrices(id, time = NULL, X = NULL, Y)
id |
vector of subjects id |
time |
vector of time occasions |
X |
matrix of covariates in long format |
Y |
matrix of responses in long format |
XX |
array of covariates (n x TT x nc) |
YY |
array of responses (n x TT x r) |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
# Example based on SRHS data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long[1:1600,] head(dataSRHS) X <- cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4,dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100) Y <- dataSRHS$srhs res <- long2matrices(dataSRHS$id, X = X, Y = Y)# Example based on SRHS data # load SRHS data data(data_SRHS_long) dataSRHS <- data_SRHS_long[1:1600,] head(dataSRHS) X <- cbind(dataSRHS$gender-1, dataSRHS$race == 2 | dataSRHS$race == 3, dataSRHS$education == 4,dataSRHS$education == 5, dataSRHS$age-50, (dataSRHS$age-50)^2/100) Y <- dataSRHS$srhs res <- long2matrices(dataSRHS$id, X = X, Y = Y)
Function that transforms data in the long format to data in the wide format.
long2wide(data, nameid, namet, colx, coly, aggr = T, full = 999)long2wide(data, nameid, namet, colx, coly, aggr = T, full = 999)
data |
matrix of data |
nameid |
name of the id column |
namet |
name of the t column |
colx |
vector of the names of the columns of the covariates |
coly |
vector of the names of the columns of the responses |
aggr |
if wide aggregated format is required |
full |
number to use for missing data |
listid |
list of id for every unit |
listt |
list of the time occasions |
data_wide |
data in wide format |
XX |
array of the covariates |
YY |
array of the responses |
freq |
vector of the corresponding frequencies |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
# Example based on criminal data # load criminal data data(data_criminal_sim) # consider only the first 1000 records to shorten time out <- long2wide(data_criminal_sim[1:1000,], "id", "time", "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"), aggr = TRUE, full = 999)# Example based on criminal data # load criminal data data(data_criminal_sim) # consider only the first 1000 records to shorten time out <- long2wide(data_criminal_sim[1:1000,], "id", "time", "sex", c("y1","y2","y3","y4","y5","y6","y7","y8","y9","y10"), aggr = TRUE, full = 999)
Function to convert data with array format in data with long format.
matrices2long(Y, X1 = NULL, X2 = NULL)matrices2long(Y, X1 = NULL, X2 = NULL)
Y |
array of responses ( |
X1 |
array of covariates ( |
X2 |
array of covariates ( |
Y, X1 and X2 must have the same number of observations.
Returns a data.frame with data in long format. The first column indicates the name of the unit identifier, and the second column indicates the time occasions.
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
### Example with data on self rated health data(data_SRHS_long) SRHS <- data_SRHS_long[1:1600,] # Covariates X <- cbind(SRHS$gender-1, SRHS$race == 2 | SRHS$race == 3, SRHS$education == 4, SRHS$education == 5, SRHS$age-50, (SRHS$age-50)^2/100) # Responses Y <- SRHS$srhs res <- long2matrices(SRHS$id, X = X, Y = Y) long <- matrices2long(Y = res$YY, X1 = res$XX)### Example with data on self rated health data(data_SRHS_long) SRHS <- data_SRHS_long[1:1600,] # Covariates X <- cbind(SRHS$gender-1, SRHS$race == 2 | SRHS$race == 3, SRHS$education == 4, SRHS$education == 5, SRHS$age-50, (SRHS$age-50)^2/100) # Responses Y <- SRHS$srhs res <- long2matrices(SRHS$id, X = X, Y = Y) long <- matrices2long(Y = res$YY, X1 = res$XX)
'MCbasic'
An S3 class object created by lmestMc function for the Markov chain (MC) model without covariates.
lk |
maximum log-likelihood |
piv |
estimate of initial probability vector |
Pi |
estimate of transition probability matrices |
np |
number of free parameters |
aic |
value of the Akaike Information Criterion for model selection |
bic |
value of the Bayesian Information Criterion for model selection |
Fy |
estimated marginal distribution of the response variable ats each time occasion |
n |
number of observations in the data |
TT |
number of time occasions |
modBasic |
model on the transition probabilities: default 0 for time-heterogeneous transition matrices, 1 for time-homogeneous transition matrices, 2 for partial time homogeneity based on two transition matrices one from 2 to (TT-1) and the other for TT |
sepiv |
standard errors for the initial probabilities |
sePi |
standard errors for the transition probabilities |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
'MCcov'
An S3 class object created by lmestMc function for Markov chain (MC) model for categorical responses in long format with covariates.
lk |
maximum log-likelihood |
Be |
estimated array of the parameters affecting the logit for the initial probabilities |
Ga |
estimated array of the parameters affecting the logit for the transition probabilities |
np |
number of free parameters |
aic |
value of the Akaike Information Criterion (AIC) for model selection |
bic |
value of the Bayesian Information Criterion (BIC) for model selection |
n |
number of observations in the data |
TT |
number of time occasions |
seBe |
standard errors for |
seGa |
standard errors for |
Piv |
estimate of initial probability matrix |
PI |
estimate of transition probability matrices |
call |
command used to call the function |
data |
data frame given in input |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Longitudinal dataset in long format deriving from the National Longitudinal Survey of Youth with information about 581 individuals followed from 1990 to 1994.
data(NLSYlong)data(NLSYlong)
A data frame with 1743 observations on the following 12 variables.
momagemother's age at birth.
gender0 if male, 1 if female.
childagechild's age at first interview.
hispanic1 if child is Hispanic, 0 if not.
black1 if child is black, 0 if not.
momwork1 if mother works, 0 if not.
married1 if parents are married, 0 if not.
timeoccasion of observation.
antia measure of antisocial behavior measured on a scale from 0 to 6.
selfa measure of self-esteem measured on a scale from 6 to 24.
pova time varying variable assuming value 1 if family is in poverty, 0 if not.
idsubject id.
https://www.nlsinfo.org/content/cohorts/nlsy79
The wide format of this dataset is downloadable from the package 'panelr'.
data(NLSYlong)data(NLSYlong)
Plots for outputs of LMest objects: LMbasic, LMbasiccont, LMlatent, LMlatentcont, and LMsearch
## S3 method for class 'LMbasic' plot(x, what = c("modSel", "CondProb", "transitions","marginal"), verbose=interactive(),...) ## S3 method for class 'LMlatent' plot(x, what = c("modSel", "CondProb", "transitions","marginal"), verbose=interactive(),...) ## S3 method for class 'LMbasiccont' plot(x, what = c("modSel", "density", "transitions","marginal"), components,verbose=interactive(),...) ## S3 method for class 'LMlatentcont' plot(x, what = c("modSel", "density", "transitions","marginal"), components, verbose=interactive(),...) ## S3 method for class 'LMsearch' plot(x,...)## S3 method for class 'LMbasic' plot(x, what = c("modSel", "CondProb", "transitions","marginal"), verbose=interactive(),...) ## S3 method for class 'LMlatent' plot(x, what = c("modSel", "CondProb", "transitions","marginal"), verbose=interactive(),...) ## S3 method for class 'LMbasiccont' plot(x, what = c("modSel", "density", "transitions","marginal"), components,verbose=interactive(),...) ## S3 method for class 'LMlatentcont' plot(x, what = c("modSel", "density", "transitions","marginal"), components, verbose=interactive(),...) ## S3 method for class 'LMsearch' plot(x,...)
x |
an object of class |
what |
a string indicating the type of plot. A detailed description is provided in the ‘Details’ section. |
components |
An integer or a vector of integers specifying the components (latent states) to be selected for the "density" plot. |
verbose |
A logical controlling if a text progress bar is displayed during the
fitting procedure. By default is |
... |
Unused argument. |
The type of plots are the following:
"modSel" |
plot of values of the Bayesian Information Criterion and of the Akaike Information |
| Criterion for model selection | |
"CondProb" |
plot of the estimated conditional response probabilities |
"density" |
plot of the overall estimated density for continuous responses, with weights given by |
| the estimated marginal distribution of the latent variable. For multivariate continuous | |
responses a contour plot is provided. If the argument components is specified, the |
|
| density plot for the selected components results | |
"transitions" |
path diagram of the estimated transition probabilities |
"marginal" |
plot of the estimated marginal distribution of the latent variable |
If argument what is not specified, a menu of choices is proposed in an interactive session.
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
## Not run: ### Plot of basic LM model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:3, start = 1, modBasic = 1, seed = 123) out summary(out) plot(out) ### Plot of basic LM model for continuous responses data(data_long_cont) out1 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, modBasic=1, tol=10^-5) plot(out1,what="modSel") plot(out1,what="density") plot(out1,what="density",components=c(1,3)) ## End(Not run)## Not run: ### Plot of basic LM model data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 1:3, start = 1, modBasic = 1, seed = 123) out summary(out) plot(out) ### Plot of basic LM model for continuous responses data(data_long_cont) out1 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k = 1:5, modBasic=1, tol=10^-5) plot(out1,what="modSel") plot(out1,what="density") plot(out1,what="density",components=c(1,3)) ## End(Not run)
Given the output, it is written in a readable form
## S3 method for class 'LMbasic' print(x, ...) ## S3 method for class 'LMbasiccont' print(x, ...) ## S3 method for class 'LMlatent' print(x, ...) ## S3 method for class 'LMlatentcont' print(x, ...) ## S3 method for class 'LMmanifest' print(x, ...) ## S3 method for class 'LMmixed' print(x, ...) ## S3 method for class 'MCbasic' print(x, ...) ## S3 method for class 'MCcov' print(x, ...) ## S3 method for class 'LMsearch' print(x, modSel = "BIC",...)## S3 method for class 'LMbasic' print(x, ...) ## S3 method for class 'LMbasiccont' print(x, ...) ## S3 method for class 'LMlatent' print(x, ...) ## S3 method for class 'LMlatentcont' print(x, ...) ## S3 method for class 'LMmanifest' print(x, ...) ## S3 method for class 'LMmixed' print(x, ...) ## S3 method for class 'MCbasic' print(x, ...) ## S3 method for class 'MCcov' print(x, ...) ## S3 method for class 'LMsearch' print(x, modSel = "BIC",...)
x |
output from |
modSel |
a string indicating the model selection criteria: |
... |
further arguments passed to or from other methods |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
Longitudinal dataset deriving from the Panel Study of Income Dynamics (PSID) from 1987 to 1993.
data(PSIDlong)data(PSIDlong)
A data frame with 1446 observations on the following variables.
idsubject id.
occasion of observation.
Y1Fertilityindicating whether a woman had given birth to a child in a certain year 1 for "yes", 0 for "no".
Y2Employmentindicating whether she was employed 1 for "yes", 0 for "no".
X1Racedummy variable equal to 1 for a "black" woman, 0 for "other".
X2Ageage in 1986, rescaled by its maximum value.
X3Age2squared age.
X4Educationnumber of years of schooling.
X5Child1_2number of children in the family aged between 1 and 2 years, referred to the previous year.
X6Child3_5number of children in the family aged between 3 and 5 years, referred to the previous year.
X7Child6_13number of children in the family aged between 6 and 13 years, referred to the previous year.
X8Child14number of children in the family aged over 14 years, referred to the previous year.
X9Incomeincome of the husband (in dollars, referred to the previous year, divided by 1,000.
https://psidonline.isr.umich.edu
This dataset is downloadable through the package 'psidR'.
data(PSIDlong)data(PSIDlong)
Longitudinal dataset deriving from the Russia Longitudinal Monitoring Survey (RLMS) about job satisfaction measured by an ordinal variable at seven different occasions with five categories, 1 for “absolutely satisfied”, 2 for “mostly satisfied”, 3 for “neutral”, 4 for “not very satisfied”, and 5 for “absolutely unsatisfied”.
data(RLMSdat)data(RLMSdat)
A data frame with 1718 observations on the following 7 variables.
IKSJQreported job satisfaction at the 1st occasion
IKSJRreported job satisfaction at the 2nd occasion
IKSJSreported job satisfaction at the 3rd occasion
IKSJTreported job satisfaction at the 4th occasion
IKSJUreported job satisfaction at the 5th occasion
IKSJVreported job satisfaction at the 6th occasion
IKSJWreported job satisfaction at the 7th occasion
http://www.cpc.unc.edu/projects/rlms-hse, https://www.hse.ru/org/hse/rlms
Russia Longitudinal Monitoring survey, RLMS-HSE, conducted by Higher School of Economics and ZAO "Demoscope" together with Carolina Population Center, University of North Carolina at Chapel Hill and the Institute of Sociology RAS
data(RLMSdat)data(RLMSdat)
Longitudinal dataset in long format deriving from the Russia Longitudinal Monitoring Survey (RLMS, from Round XVII to Round XXIII, collected from 2008 to 2014) about job satisfaction measured by an ordinal variable at seven different occasions with five categories, 1 for “absolutely satisfied”, 2 for “mostly satisfied”, 3 for “neutral”, 4 for “not very satisfied”, and 5 for “absolutely unsatisfied”.
data(RLMSlong)data(RLMSlong)
A data frame with 1718 observations on the following 7 variables.
timeoccasion of observation.
idsubject id.
rlmssee RLMSdat.
valuereported job satisfaction at different time occasions coded as 1 for “absolutely satisfied”, 2 for “mostly satisfied”, 3 for “neutral”, 4 for “not very satisfied”, 5 for “absolutely unsatisfied”.
http://www.cpc.unc.edu/projects/rlms-hse, https://www.hse.ru/org/hse/rlms
Russia Longitudinal Monitoring survey, RLMS-HSE, conducted by Higher School of Economics and ZAO "Demoscope" together with Carolina Population Center, University of North Carolina at Chapel Hill and the Institute of Sociology RAS
data(RLMSlong)data(RLMSlong)
Function to compute standard errors for the parameter estimates.
se(est, ...) ## S3 method for class 'LMbasic' se(est, ...) ## S3 method for class 'LMbasiccont' se(est, ...) ## S3 method for class 'LMlatent' se(est, ...) ## S3 method for class 'LMlatentcont' se(est, ...)se(est, ...) ## S3 method for class 'LMbasic' se(est, ...) ## S3 method for class 'LMbasiccont' se(est, ...) ## S3 method for class 'LMlatent' se(est, ...) ## S3 method for class 'LMlatentcont' se(est, ...)
est |
|
... |
further arguments |
Standard errors for estimates in est object.
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
## Not run: # LM model for categorical responses without covariates data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, modBasic = 1, out_se = FALSE) out.se <- se(out) out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, modBasic = 1, out_se = TRUE) out1.se <- se(out1) # LM model for categorical responses with covariates on the latent model out2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) out2.se <- se(out2) # LM model for continous responses without covariates data(data_long_cont) out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k =3, modBasic = 1, tol = 10^-5) out3.se <- se(out3) # LM model for continous responses with covariates out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2 | X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out4.se <- se(out4) ## End(Not run)## Not run: # LM model for categorical responses without covariates data("data_SRHS_long") SRHS <- data_SRHS_long[1:2400,] # Categories rescaled to vary from 0 (“poor”) to 4 (“excellent”) SRHS$srhs <- 5 - SRHS$srhs out <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, modBasic = 1, out_se = FALSE) out.se <- se(out) out1 <- lmest(responsesFormula = srhs ~ NULL, index = c("id","t"), data = SRHS, k = 3, modBasic = 1, out_se = TRUE) out1.se <- se(out1) # LM model for categorical responses with covariates on the latent model out2 <- lmest(responsesFormula = srhs ~ NULL, latentFormula = ~ I(gender - 1) + I( 0 + (race == 2) + (race == 3)) + I(0 + (education == 4)) + I(0 + (education == 5)) + I(age - 50) + I((age-50)^2/100), index = c("id","t"), data = SRHS, k = 2, paramLatent = "multilogit", start = 0) out2.se <- se(out2) # LM model for continous responses without covariates data(data_long_cont) out3 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, index = c("id", "time"), data = data_long_cont, k =3, modBasic = 1, tol = 10^-5) out3.se <- se(out3) # LM model for continous responses with covariates out4 <- lmestCont(responsesFormula = Y1 + Y2 + Y3 ~ NULL, latentFormula = ~ X1 + X2 | X1 + X2, index = c("id", "time"), data = data_long_cont, k = 3, output = TRUE) out4.se <- se(out4) ## End(Not run)
Function that searches for the global maximum of the log-likelihood of different models given a vector of possible number of states to try for.
The function is no longer maintained. Please look at lmestSearch function.
search.model.LM(version = c("basic","latent","manifest","basic.cont", "latent.cont"), kv, ..., nrep = 2, tol1 = 10^-5, tol2 = 10^-10,out_se = FALSE)search.model.LM(version = c("basic","latent","manifest","basic.cont", "latent.cont"), kv, ..., nrep = 2, tol1 = 10^-5, tol2 = 10^-10,out_se = FALSE)
version |
model to be estimated ("basic" = basic LM model (est_lm_basic function); "latent" = LM model with covariates in the distribution of the latent process (est_lm_cov_latent function); "manifest" = LM model with covariates in the measurement model (est_lm_cov_maifest function),"basic.cont" = basic LM model for continuous outcomes (est_lm_basic_cont function); "latent.cont" = LM model for continuous outcomes with covariates in the distribution of the latent process (est_lm_cov_latent_cont function)) |
kv |
vector of possible number of latent states |
... |
additional arguments to be passed based on the model to be estimated (see details) |
nrep |
number of repetitions of each random initialization |
tol1 |
tolerance level for checking convergence of the algorithm in the random initializations |
tol2 |
tolerance level for checking convergence of the algorithm in the last deterministic initialization |
out_se |
TRUE for computing information matrix and standard errors |
The function combines deterministic and random initializations strategy to reach the global maximum of the model log-likelihood. It uses one deterministic initialization (start=0) and a number of random initializations (start=1) proportional to the number of latent states. The tolerance level is set equal to 10^-5. Starting from the best solution obtained in this way, a final run is performed (start=2) with a default tolerance level equal to 10^-10.
Arguments in ... depend on the model to be estimated. They match the arguments to be passed to functions est_lm_basic, est_lm_cov_latent, est_lm_cov_manifest, est_lm_basic_cont, or est_lm_cov_latent_cont.
out.single |
output of each single model (as from |
aicv |
value of AIC index for each k in kv |
bicv |
value of BIC index for each k in kv |
lkv |
value of log-likelihood for each k in kv |
Francesco Bartolucci, Silvia Pandolfi, University of Perugia (IT), http://www.stat.unipg.it/bartolucci
## Not run: # example for est_lm_basic data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # Search Basic LM model res <- search.model.LM("basic", kv = 1:4, S, yv, mod = 1) summary(res) ## End(Not run)## Not run: # example for est_lm_basic data(data_drug) data_drug <- as.matrix(data_drug) S <- data_drug[,1:5]-1 yv <- data_drug[,6] n <- sum(yv) # Search Basic LM model res <- search.model.LM("basic", kv = 1:4, S, yv, mod = 1) summary(res) ## End(Not run)
Summary methods
## S3 method for class 'LMbasic' summary(object, ...) ## S3 method for class 'LMbasiccont' summary(object, ...) ## S3 method for class 'LMlatent' summary(object, ...) ## S3 method for class 'LMlatentcont' summary(object, ...) ## S3 method for class 'LMmanifest' summary(object, ...) ## S3 method for class 'LMmixed' summary(object, ...) ## S3 method for class 'MCbasic' summary(object, ...) ## S3 method for class 'MCcov' summary(object, ...) ## S3 method for class 'LMsearch' summary(object,...)## S3 method for class 'LMbasic' summary(object, ...) ## S3 method for class 'LMbasiccont' summary(object, ...) ## S3 method for class 'LMlatent' summary(object, ...) ## S3 method for class 'LMlatentcont' summary(object, ...) ## S3 method for class 'LMmanifest' summary(object, ...) ## S3 method for class 'LMmixed' summary(object, ...) ## S3 method for class 'MCbasic' summary(object, ...) ## S3 method for class 'MCcov' summary(object, ...) ## S3 method for class 'LMsearch' summary(object,...)
object |
output from |
... |
further arguments passed to or from other methods |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini
lmestData
Methods for lmestData object providing basic descriptive statistics (summary) and plots.
## S3 method for class 'lmestData' summary(object, type = c("all","cross", "year"), dataSummary = c("all", "responses", "manifest", "initial", "transition"), varType = rep("c", x$d), digits = getOption("digits"), maxsum = 10, maxobs = 20, ...) ## S3 method for class 'lmestData' plot(x, typePlot = c("s", "sh"), dataPlots = c("all", "responses", "manifest", "initial", "transition"), ...) ## S3 method for class 'lmestData' print(x, ...)## S3 method for class 'lmestData' summary(object, type = c("all","cross", "year"), dataSummary = c("all", "responses", "manifest", "initial", "transition"), varType = rep("c", x$d), digits = getOption("digits"), maxsum = 10, maxobs = 20, ...) ## S3 method for class 'lmestData' plot(x, typePlot = c("s", "sh"), dataPlots = c("all", "responses", "manifest", "initial", "transition"), ...) ## S3 method for class 'lmestData' print(x, ...)
object |
an object of class |
x |
an object of class |
type |
type of summary to print. |
dataSummary |
a string indicating whether summary is returned: |
varType |
a string vector of lengh equal to the number of variables, "c" for continuous and "d" for discrete, indicating wich varaibles are continuos and which are discrete |
digits |
the number of significant digits |
maxsum |
an integer value indicating the maximum number of levels to print |
maxobs |
an integer value indicating the maximun number of observation in which the summary statistics are reported for each observation |
typePlot |
a string indicating the type of plot. "s" plots a scaterplot matrix. "sh" plots a scatterplot matrix with the histogram for each variable in the diagonal |
dataPlots |
a string indicating whether the plot is returned: |
... |
further arguments |
Francesco Bartolucci, Silvia Pandolfi, Fulvia Pennoni, Alessio Farcomeni, Alessio Serafini