| Title: | Estimators for Two-Sample Capture-Recapture Studies |
|---|---|
| Description: | A comprehensive implementation of Petersen-type estimators and its many variants for two-sample capture-recapture studies. A conditional likelihood approach is used that allows for tag loss; non reporting of tags; reward tags; categorical, geographical and temporal stratification; partial stratification; reverse capture-recapture; and continuous variables in modeling the probability of capture. Many examples from fisheries management are presented. |
| Authors: | Carl Schwarz [aut, cre] |
| Maintainer: | Carl Schwarz <[email protected]> |
| License: | GPL-2 |
| Version: | 2024.6.1 |
| Built: | 2024-11-28 06:31:55 UTC |
| Source: | CRAN |
Convert capture history data to n, m and u for use in BTSPAS
cap_hist_to_n_m_u(data, sep = "..")cap_hist_to_n_m_u(data, sep = "..")
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
sep |
Separator used between strata in cap_hit |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of the format
xx..yy is a capture_history where xx and yy are the temporal stratum
(e.g., julian week) and '..' separates
the two temporal strata.
If a fish is released in temporal stratum and never captured again, then yy is set to 0;
if a fish is newly captured in temporal stratum yy, then xx is set to zero.
For example, a capture history of 23..23 indicates animals released in temporal stratum
23 and recaptured in temporal stratum 23; a capture history of 23..00
indicates animals released in temporal stratum
23 and never seen again; a capture history of 00..23
indicates animals newly captured in temporal stratum
23 at the second sampling event.
. In the diagonal case, fish are only recovered in the same temporal stratum. In the non-diagonal case, fish are allowed to move among temporal strata.
It is not necessary to label the temporal strata starting at 1; BTSPAS will treat the smallest value of the temporal strata seen as the first stratum and will interpolate for temporal strata without any data. Temporal strata labels should be numeric, i.e., do NOT use A, B, C etc.
A list with entries for the stratum index, n (number released), m matrix of recoveries in the current, next, etc stratum, and u (number of unmarked fish) captured in this recovery stratum.
data(data_btspas_diag1) cap_hist_to_n_m_u(data_btspas_diag1) data(data_btspas_nondiag1) cap_hist_to_n_m_u(data_btspas_nondiag1)data(data_btspas_diag1) cap_hist_to_n_m_u(data_btspas_diag1) data(data_btspas_nondiag1) cap_hist_to_n_m_u(data_btspas_nondiag1)
This is the first diagonal case dataset from BTSPAS.
data(data_btspas_diag1)data(data_btspas_diag1)
data_btspas_diag1A data frame with many rows and 3 columns
cap_hist.Capture history of the form ‘jweek..jweek’ for fish that are recaptured in the same julian week; '0..jweek' for unmarked fish newly captured in that julian week ; 'jweek..0' for fish released in the julian week but never recaptured.
freq.Number of fish with this history.
logflowlog(flow) for this julian week
Consider an experiment to estimate the number of outgoing smolts on a small river. The run of smolts extends over several weeks. As smolts migrate, they are captured and marked with individually numbered tags and released at the first capture location using, for example, a fishwheel. The migration continues, and a second fishwheel takes a second sample several kilometers down stream. At the second fishwheel, the captures consist of a mixture of marked (from the first fishwheel) and unmarked fish.
The efficiency of the fishwheels varies over time in response to stream flow, run size passing the wheel and other uncontrollable events. So it is unlikely that the capture probabilities are equal over time at either location, i.e. are heterogeneous over time.
We suppose that we can temporally stratify the data into, for example, weeks, where the
capture-probabilities are (mostly) homogeneous at each wheel in each week. Furthermore, suppose that
fish captured and marked in each week tend to migrate together so that they are
captured in a single subsequent stratum. For example,
suppose that in each julian week , fish are marked and released above the rotary screw trap.
Of these, are recaptured. All recaptures take place in the week of release,
i.e. the matrix of releases and recoveries is diagonal.
The and establish the capture efficiency of the second trap in julian week .
At the same time, unmarked fish are captured at the screw trap.
Capture-efficiency may be related to flow, so the log(flow) is also recorded.
This is the first non-diagonal case dataset from BTSPAS.
data(data_btspas_nondiag1)data(data_btspas_nondiag1)
data_btspas_nondiag1A data frame with many rows and 3 columns
cap_hist.Capture history of the form ‘week1..week2’ for fish that are released on week 1 and recaptured on week 2 ; '0..week22' for unmarked fish newly captured in week 2; 'week1..0' for fish released in week 1 but never recaptured.
freq.Number of fish with this history.
Incoming sockeye salmon are captured on a first wheel, tagged with color tags that vary by week, and recaptured on an upriver weir. The upriver weir was not in operation for the first few weeks.
This is the data from Hyun et al (2012). In August and September 2007, the period just before the spawning run, adult kokanee were collected by beach seining in the upper arm of the lake near the confluence with the Metolius River. Fish were tagged with nonpermanent, plastic T-bar anchor tags and then were released back into the lake. Randomly selected fish received single tags of one color, while the other fish received two tags of a second color (i.e., the double tags were identical in color). In late September through October, spawning ground surveys were conducted by 2–3 people walking abreast in a downstream direction (or floating, in sections where the water depth and flow were too great to allow walking). Instead of being physically recaptured, the fish were resighted as they swam freely in the clear, relatively shallow water within the spawning areas of the river. The total number of fish observed with or without a tag (or tags) was recorded for each section, and information on the number and color of tags for each marked fish was also noted.
data(data_kokanee_tagloss)data(data_kokanee_tagloss)
data_kokanee_taglossA data frame with many rows and 2 columns
cap_hist.Capture history (1000, 1010, 1100, 1110, 1111).
freq.Number of fish with this history. Always 1
Because fish were not handled, it is not possible to know which of the double tags were lost, and so only models with equal retention probabilities and non-distinguishable double tags should be fit. Note that the capture history for a lost of 1 indistinguishable tag is 111X rather than 1110 or 1101 (both of which are not allowed in the model with indistinguishable double tags)
This is the data provided by Kaitlyn Dionne, DFO. Arbeider et al (2020) proposed to estimate the run size of Lower Fraser River Coho (LFC) using a geographically stratified reverse-capture method. Briefly, a LFC coho swim upstream, they are sampled near New Westminister, BC, which is downstream from several major rivers up which are large spawning populations. These sample fish are assigned to the spawning population using genetic and other methods. These spawning populations are identified as the Chilliwack Hatchery (denoted C), the Lilloet River natural spawning population (denoted L), the Nicomen Slough population (denote N) and all other population (denoted as 0). Notice that the sample fish at New Westminister are NOT physically tagged, and population assignment is through genetic and other measures. The upstream migration extends over two months (September to October) and is divided into 3 temporal strata corresponding to Early (denoted 1E), Peak (denoted 2P) and Late (denoted 3L). The digits 1, 2, 3 in front of the codes ensures that the temporal strata are sorted temporally, but this is merely a convenience and does not affect the results. The spawning populations at C, L, and N are estimated by a variety of methods (see Arbeider, et al. 2020). Each of the population estimates also has an estimated (which will be ignored for now).
data(data_lfc_reverse)data(data_lfc_reverse)
data_lfc_reverse
A data frame with many rows and 4 columns
cap_hist.Capture history with possible histories as noted below
freq.Number of fish with this history.
SE.SE of the number of fish with this history. Only available for total escapement to C, L, N
Fish were tagged on the spawning grounds and recovered in the summer gillnet assessment. Fish were double tagged, and a tag loss analysis showed that tag loss was negligible. It will be ignored here. Length was measured a both times and didn't not change very much between the two sampling occasions. The value recorded below is the average of the two lengths if both lengths were present. Fish that were not sexed or measured for length are ignored and not included
data(data_NorthernPike)data(data_NorthernPike)
data_NorthernPikeA data frame with many rows and 4 columns
cap_hist.Capture history (10, 01, or 11). Note that
; ; and
freq.Number of fish with this history. Always 1
Sex.Sex of the fish. M=Male; F=Female
LengthLength of the fish in inches.
Fish were tagged on the spawning grounds and recovered in the summer gillnet assessment. Fish were double tagged and the double tagging information is included here. Length was measured a both times and didn't not change very much between the two sampling occasions. The value recorded below is the average of the two lengths if both lengths were present. Fish that were not sexed or measured for length are ignored and not included
data(data_NorthernPike_tagloss)data(data_NorthernPike_tagloss)
data_NorthernPike_taglossA data frame with many rows and 4 columns
cap_hist.Capture history (10, 01, or 11). Note that
; ; and
freq.Number of fish with this history. Always 1
Sex.Sex of the fish. M=Male; F=Female
LengthLength of the fish in inches.
Ricker (1975) gives an example of work by Knut Dahl on estimating the number of brown trout
(Salmo truitta) in some small Norwegian tarns. Between 100 and 200 trout were caught by
seining, marked by removing a fin (an example of a batch mark) and distributed
in a systematic fashion around the tarn to encourage mixing.
A total of =109 fish were
captured, clipped and released,
=177 fish were captured at the second occasion, and =57
marked fish were recovered.
data(data_rodli)data(data_rodli)
data_rodliA data frame with 3 rows and 2 columns:
cap_hist.Capture history (10, 01, or 11). Note that
; ; and
freq.Number of fish with this history
This is simulated data with the parameter values given in details.
data(data_sim_reward)data(data_sim_reward)
data_sim_rewardA data frame with many rows and 2 columns
cap_hist.Capture history (1000, 1010, 0P00, 0P0P, 0010).
freq.Number of fish with this history.
data_sim_reward <-LP_TL_simulate(
dt_type=dt_type, # permanent tag
N=10000,
cov1=function(N) {rep(1,N)},
cov2=function(cov1) {rep(1, length(cov1))},
p1 =function(cov1, cov2){rep(.1, length(cov1))},
pST =function(cov1, cov2){rep(.75,length(cov1))},
rho1=function(cov1, cov2){rep(.70,length(cov1))},
rho2=function(cov1, cov2){rep(1, length(cov1))}, # permanent second tag
p2 =function(cov1, cov2){rep(.1, length(cov1))},
seed=45985, trace=FALSE)
# we don't have fish with both tags
data_sim_reward$cap_hist <- gsub("1P", "0P", data_sim_reward$cap_hist)
This is simulated data with the parameter values given in details.
data(data_sim_tagloss_t2perm)data(data_sim_tagloss_t2perm)
data_sim_tagloss_t2permA data frame with many rows and 2 columns
cap_hist.Capture history (1000, 1010, 1P00, 1P0P, 1P1P, 0010).
freq.Number of fish with this history.
data_sim_tagloss_t2perm <-LPTL_simulate(
dt_type="t2perm", # second permanent
N=10000,
cov1=function(N) {rep(1,N)},
cov2=function(cov1) {rep(1, length(cov1))},
p1 =function(cov1, cov2){rep(.1, length(cov1))},
pST =function(cov1, cov2){rep(.25,length(cov1))},
rho1=function(cov1, cov2){rep(.70,length(cov1))},
rho2=function(cov1, cov2){rep(1, length(cov1))}, # permanent tag
p2 =function(cov1, cov2){rep(.1, length(cov1))},
seed=234523, trace=FALSE)
This is simulated data with the parameter values given in the description.
data(data_sim_tagloss_twoD)data(data_sim_tagloss_twoD)
data_sim_tagloss_twoDA data frame with many rows and 2 columns
cap_hist.Capture history (1000, 1010, 1100, 1110, 1101, 1111).
freq.Number of fish with this history.
data_sim_tagloss_twoD <-LPTL_simulate(
dt_type="twoD", # two distinguishable tags
N=10000,
cov1=function(N) {rep(1,N)},
cov2=function(cov1) {rep(1, length(cov1))},
p1 =function(cov1, cov2){rep(.1, length(cov1))},
pST =function(cov1, cov2){rep(.25,length(cov1))},
rho1=function(cov1, cov2){rep(.70,length(cov1))},
rho2=function(cov1, cov2){rep(.80,length(cov1))},
p2 =function(cov1, cov2){rep(.1, length(cov1))},
seed=234523, trace=FALSE)
Incoming sockeye salmon are captured on a first wheel, tagged with color tags that vary by week, and recaptured on several spawning areas.
data(data_spas_harrison)data(data_spas_harrison)
data_spas harrisonA data frame with many rows and 2 columns
cap_hist.Capture history of the form ‘week..area’ for fish that are released on week and recaptured area ; '0..area' for unmarked fish newly captured in area; 'week..0' for fish released in week but never recaptured.
freq.Number of fish with this history.
Data used in Premarathna, W.A.L., Schwarz, C.J., Jones, T.S. (2018) Partial stratification in two-sample capture–recapture experiments. Environmetrics, 29:e2498. https://doi.org/10.1002/env.2498
data(data_wae_is_long)data(data_wae_is_long)
data_wae_is_long
A data frame with many rows and 3 columns
cap_hist.Capture history with possible histories as noted below
freq.Number of fish with this history.
lengthLength of fish (inches)
Fish were tagged on the spawning grounds and recovered in the summer gillnet assessment.
Length was measured a both times and didn't not change very much between the two sampling occasions. The value recorded below is the average of the two lengths if both lengths were present.
Rather than sexing all of the fish, only a sub-sample of unmarked fish is sexed at each sampling occasion. Possible capture histories are then M0, F0, MM, FF, U0, UU, 0M, 0F
Data used in Premarathna, W.A.L., Schwarz, C.J., Jones, T.S. (2018) Partial stratification in two-sample capture–recapture experiments. Environmetrics, 29:e2498. https://doi.org/10.1002/env.2498
data(data_wae_is_short)data(data_wae_is_short)
data_wae_is_short
A data frame with many rows and 2 columns
cap_hist.Capture history with possible histories as noted below
freq.Number of fish with this history.
Data is slightly different from that in paper above because some fish did not have length measured and so were drop from data_wae_is_long and this is the condensed version of data_wae_is_long.
Fish were tagged on the spawning grounds and recovered in the summer gillnet assessment.
Rather than sexing all of the fish, only a sub-sample of unmarked fish is sexed at each sampling occasion. Possible capture histories are then M0, F0, MM, FF, U0, UU, 0M, 0F
Data from Hamazaki, T. and DeCovich, N. (2014). Application of the Genetic Mark–Recapture Technique for Run Size Estimation of Yukon River Chinook Salmon. North American Journal of Fisheries Management, 34, 276-286. DOI: 10.1080/02755947.2013.869283 This is the data from the 2011 data in Table 2 of the above paper. Estimated that total escapement to Canada (plus harvest) was 66,225 (SE 1574) Estimated that proportion of stock that was Canadian was .34644 (SE .030) We converted this into a "sample size" and number of fish with Canadian genetics that gave the same SE.
data(data_yukon_reverse)data(data_yukon_reverse)
data_yukon_reverse
A data frame with many rows and 4 columns
cap_hist.Capture history with possible histories as noted below
freq.Number of fish with this history.
SE.SE of the number of fish with this history
We assign a "class" (one of the classes above) to the results from one of the fitting methods. This class designation is only used to ensure that estimation routines have the correct type of fit when finding estimates of abundance, and model averaging only considers models of comparable class when creating the model averaging results of abundance.
fit_classes()fit_classes()
The structure of an object of the above classes is roughly comparable across classes. The object should be a list with the following objects
summary A data frame with the model for the parameters of the model; the conditional log-likelihood; the number of parameters; the number of parameters, and method used to fit the model
data A data frame with the raw data used in the fit
fit Results of the fit including the estimates, SE, vcov, etc.
datetime Date and time the fit was done
Other objects may also be included in the list.
After a fit performed, estimates of ABUNDANCE are extracted using the xxx_est() function corresponding to the xxx_fit() function used to estimate parameters. This separation occurs because
abundance is a derived estimate; the fits are based on conditional likelihood (on the observed data) and the abundance parameter does not appear in the conditional likelihood. Abundance is usually estimated using a variation of a Horvitz-Thompson estimator.
you can obtain estimates of overall abundance, subsets of the population (e.g., sex or other strata) from the same fit, and so you don't need to do several fits to get several estimates of abundance.
NOTHING. This is not a function, but only documents how I use "classes".
Compute the logit or anti-logit.
logit(p) expit(theta)logit(p) expit(theta)
p |
probability between 0 and 1. |
theta |
logit between -infinity and +infinity |
Computed logit or anti-logit
C.J.Schwarz [email protected]
##---- compute the logit and its inverse logitp <- logit(.3) p <- expit(-.84)##---- compute the logit and its inverse logitp <- logit(.3) p <- expit(-.84)
This will take a series of LP fits and computes the usual AICc table and model weights
LP_AICc(...)LP_AICc(...)
... |
Series of LP fits |
An data frame with an AICc table and model weights etc
data(data_rodli) mt <- Petersen::LP_fit(data=data_rodli, p_model=~..time) m0 <- Petersen::LP_fit(data=data_rodli, p_model=~1) Petersen::LP_AICc(m0,mt)data(data_rodli) mt <- Petersen::LP_fit(data=data_rodli, p_model=~..time) m0 <- Petersen::LP_fit(data=data_rodli, p_model=~1) Petersen::LP_AICc(m0,mt)
This will take a previous fit and return estimates of abundance.
LP_BTSPAS_est(LP_BTSPAS_fit, parm = "Ntot", conf_level = 0.95, trace = FALSE)LP_BTSPAS_est(LP_BTSPAS_fit, parm = "Ntot", conf_level = 0.95, trace = FALSE)
LP_BTSPAS_fit |
A result of an call to fitting at BTSPAS object. |
parm |
Which parameter from the BTSPAS fix is to be extracted? |
conf_level |
The expected coverage for confidence intervals on N. |
trace |
If trace flag is set in call when estimating functions |
An list object of class LP_BTSPAS_est with the following elements
summary A data frame with the estimates of abundance, SE, and CI
datetime Date and time the fit was done
Schwarz, C. J. [email protected].
# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_diag1) # extract the strata of interest temp<- cbind(data_btspas_diag1, split_cap_hist( data_btspas_diag1$cap_hist, sep="..", make.numeric=TRUE)) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% 0:10 & temp$t2 %in% 0:10,] fit <- Petersen::LP_BTSPAS_fit_Diag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_diag1) # extract the strata of interest temp<- cbind(data_btspas_diag1, split_cap_hist( data_btspas_diag1$cap_hist, sep="..", make.numeric=TRUE)) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% 0:10 & temp$t2 %in% 0:10,] fit <- Petersen::LP_BTSPAS_fit_Diag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary
Takes the data structure as described below, and uses Bayesian methods to fit a fit a spline through the population numbers and a hierarchical model for the trap efficiencies over time. An MCMC object is also created with samples from the posterior.
LP_BTSPAS_fit_Diag( data, p_model = ~1, p_model_cov = NULL, jump.after = NULL, logitP.fixed = NULL, logitP.fixed.values = NULL, InitialSeed = ceiling(stats::runif(1, min = 0, max = 1e+06)), n.chains = 3, n.iter = 2e+05, n.burnin = 1e+05, n.sims = 2000, trace = FALSE, remove_MCMC_files = TRUE, quietly = FALSE )LP_BTSPAS_fit_Diag( data, p_model = ~1, p_model_cov = NULL, jump.after = NULL, logitP.fixed = NULL, logitP.fixed.values = NULL, InitialSeed = ceiling(stats::runif(1, min = 0, max = 1e+06)), n.chains = 3, n.iter = 2e+05, n.burnin = 1e+05, n.sims = 2000, trace = FALSE, remove_MCMC_files = TRUE, quietly = FALSE )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
p_model |
Model for the captured probabilities. This can reference
other variables in the data frame, plus a special reserved term For some models (e.g., tag loss models), the |
p_model_cov |
Data frame with covariates for the model for prob capture at second sampling event. If this
data frame is given, it requires one line for each of the temporal strata at the second sampling event (even
if missing in the |
jump.after |
A numeric vector with elements belonging to |
logitP.fixed |
A numeric vector (could be null) of the time strata
where the logit(P) would be fixed. Typically, this is used when the capture
rates for some strata are 0 and logit(P) is set to -10 for these strata. The
fixed values are given in |
logitP.fixed.values |
A numerical vector (could be null) of the fixed values for logit(P) at strata given by logitP.fixed. Typically this is used when certain strata have a 0 capture rate and the fixed value is set to -10 which on the logit scale gives $p_i$ essentially 0. Don't specify values such as -50 because numerical problems could occur when this is converted to the 0-1 scale. |
InitialSeed |
Numeric value used to initialize the random numbers used in the MCMC iterations. |
n.chains |
Number of chains to fit in the MCMC |
n.iter |
Total number of iterations |
n.burnin |
Number of burnin iterations |
n.sims |
Total number of simulations to keep in output (implies a thinning) |
trace |
Internal tracing flag. |
remove_MCMC_files |
Should the temporary MCMC files (init.txt, data.text, model.txt, CODA*txt) removed after the fit. |
quietly |
Suppress all console messages that occur during the fit. This includes the progress bar when a model that requires MCMC is fit (LP_BTSPAS_fit_Diag and LP_BTSPAS_fit_NonDiag), or a trace of the likelihood during the fit (LP_SPAS_fit). |
Use the Petersen::LP_BTSPAS_fit_NonDiag function for cases
where recaptures take place outside the stratum of release.
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of the format
xx..yy is a capture_history where xx and yy are the temporal stratum
(e.g., julian week) and '..' separates
the two temporal strata.
If a fish is released in temporal stratum and never captured again, then yy is set to 0;
if a fish is newly captured in temporal stratum yy, then xx is set to zero.
For example, a capture history of 23..23 indicates animals released in temporal stratum
23 and recaptured in temporal stratum 23; a capture history of 23..00
indicates animals released in temporal stratum
23 and never seen again; a capture history of 00..23
indicates animals newly captured in temporal stratum
23 at the second sampling event.
In the diagonal case, no fish should move between temporal strata.
It is not necessary to label the temporal strata starting at 1; BTSPAS will treat the smallest value of the temporal strata seen as the first stratum and will interpolate for temporal strata without any data. Temporal strata labels should be numeric, i.e., do NOT use A, B, C etc.
An list object of class LP_BTSPAS_fit_Diag with the following elements
summary A data frame with the information on the number of observations in the fit
data Data used in the fit
p_model, p_model_cov Information on modelling the capture probabilities at the second occasion
fit n MCMC object with samples from the posterior distribution. A series of graphs and text file are also created with summary information. Refer to the BTSPAS package for more details.
datetime Date and time the fit was done
Bonner, S. J. and Schwarz, C. J. (2021). BTSPAS: Bayesian Time Stratified Petersen Analysis System.R package version 2021.11.2.
Bonner, S. J., & Schwarz, C. J. (2011). Smoothing population size estimates for Time-Stratified Mark-Recapture experiments Using Bayesian P-Splines. Biometrics, 67, 1498-1507. doi:10.1111/j.1541-0420.2011.01599.x
# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_diag1) # extract the strata of interest temp<- cbind(data_btspas_diag1, split_cap_hist( data_btspas_diag1$cap_hist, sep="..", make.numeric=TRUE)) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% 0:10 & temp$t2 %in% 0:10,] fit <- Petersen::LP_BTSPAS_fit_Diag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_diag1) # extract the strata of interest temp<- cbind(data_btspas_diag1, split_cap_hist( data_btspas_diag1$cap_hist, sep="..", make.numeric=TRUE)) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% 0:10 & temp$t2 %in% 0:10,] fit <- Petersen::LP_BTSPAS_fit_Diag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary
Takes the data structure as described below, and uses Bayesian methods to fit a fit a spline through the population numbers and a hierarchical model for the trap efficiency over time. An MCMC object is also created with samples from the posterior.
LP_BTSPAS_fit_NonDiag( data, p_model = ~1, p_model_cov = NULL, jump.after = NULL, logitP.fixed = NULL, logitP.fixed.values = NULL, InitialSeed = ceiling(stats::runif(1, min = 0, max = 1e+06)), n.chains = 3, n.iter = 2e+05, n.burnin = 1e+05, n.sims = 2000, trace = FALSE, remove_MCMC_files = TRUE, quietly = FALSE )LP_BTSPAS_fit_NonDiag( data, p_model = ~1, p_model_cov = NULL, jump.after = NULL, logitP.fixed = NULL, logitP.fixed.values = NULL, InitialSeed = ceiling(stats::runif(1, min = 0, max = 1e+06)), n.chains = 3, n.iter = 2e+05, n.burnin = 1e+05, n.sims = 2000, trace = FALSE, remove_MCMC_files = TRUE, quietly = FALSE )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
p_model |
Model for the captured probabilities. This can reference
other variables in the data frame, plus a special reserved term For some models (e.g., tag loss models), the |
p_model_cov |
Data frame with covariates for the model for prob capture at second sampling event. If this
data frame is given, it requires one line for each of the temporal strata at the second sampling event (even
if missing in the |
jump.after |
A numeric vector with elements belonging to |
logitP.fixed |
A numeric vector (could be null) of the time strata
where the logit(P) would be fixed. Typically, this is used when the capture
rates for some strata are 0 and logit(P) is set to -10 for these strata. The
fixed values are given in |
logitP.fixed.values |
A numerical vector (could be null) of the fixed values for logit(P) at strata given by logitP.fixed. Typically this is used when certain strata have a 0 capture rate and the fixed value is set to -10 which on the logit scale gives $p_i$ essentially 0. Don't specify values such as -50 because numerical problems could occur when this is converted to the 0-1 scale. |
InitialSeed |
Numeric value used to initialize the random numbers used in the MCMC iterations. |
n.chains |
Number of chains to fit in the MCMC |
n.iter |
Total number of iterations |
n.burnin |
Number of burnin iterations |
n.sims |
Total number of simulations to keep in output (implies a thinning) |
trace |
Internal tracing flag. |
remove_MCMC_files |
Should the temporary MCMC files (init.txt, data.text, model.txt, CODA*txt) removed after the fit. |
quietly |
Suppress all console messages that occur during the fit. This includes the progress bar when a model that requires MCMC is fit (LP_BTSPAS_fit_Diag and LP_BTSPAS_fit_NonDiag), or a trace of the likelihood during the fit (LP_SPAS_fit). |
Use the Petersen::LP_BTSPAS_fit_Diag function for cases
where recaptures take place in a single stratum (diagonal case).
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of the format
xx..yy is a capture_history where xx and yy are the temporal stratum
(e.g., julian week) and '..' separates
the two temporal strata.
If a fish is released in temporal stratum and never captured again, then yy is set to 0;
if a fish is newly captured in temporal stratum yy, then xx is set to zero.
For example, a capture history of 23..23 indicates animals released in temporal stratum
23 and recaptured in temporal stratum 23; a capture history of 23..00
indicates animals released in temporal stratum
23 and never seen again; a capture history of 00..23
indicates animals newly captured in temporal stratum
23 at the second sampling event.
In the non-diagonal case, fish are allowed to move among temporal strata.
It is not necessary to label the temporal strata starting at 1; BTSPAS will treat the smallest value of the temporal strata seen as the first stratum and will interpolate for temporal strata without any data. Temporal strata labels should be numeric, i.e., do NOT use A, B, C etc.
An list object of class LP_BTSPAS_fit_Diag with the following elements
summary A data frame with the information on the number of observations in the fit
data Data used in the fit
p_model, p_model_cov Information on modelling the capture probabilities at the second occasion
fit n MCMC object with samples from the posterior distribution. A series of graphs and text file are also created with summary information. Refer to the BTSPAS package for more details.
datetime Date and time the fit was done
Bonner, S. J. and Schwarz, C. J. (2021). BTSPAS: Bayesian Time Stratified Petersen Analysis System.R package version 2021.11.2.
Bonner, S. J., & Schwarz, C. J. (2011). Smoothing population size estimates for Time-Stratified Mark-Recapture experiments Using Bayesian P-Splines. Biometrics, 67, 1498-1507. doi:10.1111/j.1541-0420.2011.01599.x
# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_nondiag1) temp<- cbind(data_btspas_nondiag1, split_cap_hist( data_btspas_nondiag1$cap_hist, sep="..", make.numeric=TRUE)) xtabs(~t1, data=temp) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% c(0, 27:32) & temp$t2 %in% c(0, 27:32),] fit <- Petersen::LP_BTSPAS_fit_NonDiag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary# NOTE. To keep execution time to a small value as required by CRAN # I've made a very small example. # Additionally, I've set the number of MCMC chains, iterations, burning, simulation to save to # small values. Proper mixing may not have occurred yet. # When using this routine, you likely want to the use the default values # for these MCMC parameters. data(data_btspas_nondiag1) temp<- cbind(data_btspas_nondiag1, split_cap_hist( data_btspas_nondiag1$cap_hist, sep="..", make.numeric=TRUE)) xtabs(~t1, data=temp) # only use data up to week 10 to keep example small temp <- temp[ temp$t1 %in% c(0, 27:32) & temp$t2 %in% c(0, 27:32),] fit <- Petersen::LP_BTSPAS_fit_NonDiag( temp, p_model=~1, InitialSeed=23943242, # the number of chains and iterations are too small to be useful # they are set to a small number to pare execution time to <5 seconds for an example n.chains=2, n.iter=20000, n.burnin=1000, n.sims=100, quietly=TRUE ) fit$summary # now get the estimates of abundance est <- Petersen::LP_BTSPAS_est (fit) est$summary
This will take a data frame of capture histories, frequencies, and a covariates and will do a non-parametric smoother for the detection probabilities as a function of the covariates and use this to estimate the population size.
LP_CL_fit( data, covariate, centers = hist(data[, covariate, drop = TRUE], breaks = "Sturges", plot = FALSE)$mids, h1 = (centers[2] - centers[1]) * 0.75, h2 = (centers[2] - centers[1]) * 0.75, conf_level = 0.95 )LP_CL_fit( data, covariate, centers = hist(data[, covariate, drop = TRUE], breaks = "Sturges", plot = FALSE)$mids, h1 = (centers[2] - centers[1]) * 0.75, h2 = (centers[2] - centers[1]) * 0.75, conf_level = 0.95 )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
covariate |
Name of continuous covariate that influences capture probabilities at each event |
centers |
Centers of bins to group the covariates. We suggest no more than 30 bins in total with fewer bins with smaller sample sizes. Of course with smaller sample sizes, a simple stratified estimator may be easier to use. |
h1, h2
|
Standard deviation of normal kernel for first sampling event. This should be between 1/2 and the 1.5x the bin width. Larger values imply more smoothing. Smaller values imply less smoothing. |
conf_level |
The expected coverage for confidence intervals on N. |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of length 2.
10 Animals tagged but never seen again.
11 Animals tagged and recaptured and tag present at event 2.
01 Animals captured at event 2 that appear to be untagged.
An list object of class LP_CL_fit with abundance estimates and other information with the following elements
summary A data frame with the estimates of abundance, SE, and CI
fit Details on the Chen and Lloyd fit including the smoothed estimates of catchability, estimates abundance by category classes, estimates of total abundance, plots of the estimated abundance curve and catchability curves, etc.
datetime Date and time the fit was done
SX Chen, CJ Lloyd (2000). A nonparametric approach to the analysis of two-stage mark-recapture experiments. Biometrika, 87, 633–649. doi:10.1093/biomet/87.3.633.
library(Petersen) data(data_NorthernPike) res <- LP_CL_fit(data_NorthernPike, "length") res$summarylibrary(Petersen) data(data_NorthernPike) res <- LP_CL_fit(data_NorthernPike, "length") res$summary
This will take a previous fit and return estimates of abundance. The population abundance is estimated using a Horvitz-Thompson type estimator and the user can request abundance estimates for sub-sets of the population.
LP_est(LP_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)LP_est(LP_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)
LP_fit |
A result of an LP_fit() call. |
N_hat |
A formula requesting which abundance estimates should be formed. The formula are
expanded against the data frame to determine which records form part of the abundance estimate.
The formula is evaluated against the Some familiarity on how In addition to the variables in the |
conf_level |
The expected coverage for confidence intervals on N. |
trace |
If trace flag is set in call when estimating functions |
An list object with abundance estimates and other information with the following elements
summary Data frame with abundance estimates, their SE, and CIs as requested
detail List with many components, including the rawdata, model fitting information, observed and expected values, residual plot, etc
datetime Date and time the estimation was done from the fit.
Schwarz, C. J. [email protected].
# fit a simple Petersen model and get the estimated abundance data(data_rodli) fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) fit$summary # Now to get the estimated abundance est <- Petersen::LP_est(fit, N_hat=~1) est$summary # repeat the fit with the Chapman correction # we add an additional animal with history 11 rodli.chapman <- plyr::rbind.fill(data_rodli, data.frame(cap_hist="11", freq=1, comment="Added for Chapman")) rodli.chapman fit.chapman <- Petersen::LP_fit(data=rodli.chapman, p_model=~..time) fit.chapman$summary # Now to get the estimated abundance est.chapman <- Petersen::LP_est(fit.chapman, N_hat=~1) est.chapman$summary # Example of simple stratification (by sex) data(data_NorthernPike) nop.red <- plyr::ddply(data_NorthernPike, c("cap_hist","Sex"), plyr::summarize, freq=sum(freq)) nop.red # reduced capture history to speed execution time of example # Fit the various models nop.fit.sex.time <- Petersen::LP_fit(nop.red, p_model=~-1+Sex:..time) nop.fit.sex.time$summary # estimate of overall abundance nop.est.ALL <- Petersen::LP_est(nop.fit.sex.time, N=~1) nop.est.ALL$summary # estimate of abundance for each sex nop.est.by.sex <- Petersen::LP_est(nop.fit.sex.time, N=~-1+Sex) nop.est.by.sex$summary # Refer to vignettes for example using continuous variable (e.g. length) to model catchability# fit a simple Petersen model and get the estimated abundance data(data_rodli) fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) fit$summary # Now to get the estimated abundance est <- Petersen::LP_est(fit, N_hat=~1) est$summary # repeat the fit with the Chapman correction # we add an additional animal with history 11 rodli.chapman <- plyr::rbind.fill(data_rodli, data.frame(cap_hist="11", freq=1, comment="Added for Chapman")) rodli.chapman fit.chapman <- Petersen::LP_fit(data=rodli.chapman, p_model=~..time) fit.chapman$summary # Now to get the estimated abundance est.chapman <- Petersen::LP_est(fit.chapman, N_hat=~1) est.chapman$summary # Example of simple stratification (by sex) data(data_NorthernPike) nop.red <- plyr::ddply(data_NorthernPike, c("cap_hist","Sex"), plyr::summarize, freq=sum(freq)) nop.red # reduced capture history to speed execution time of example # Fit the various models nop.fit.sex.time <- Petersen::LP_fit(nop.red, p_model=~-1+Sex:..time) nop.fit.sex.time$summary # estimate of overall abundance nop.est.ALL <- Petersen::LP_est(nop.fit.sex.time, N=~1) nop.est.ALL$summary # estimate of abundance for each sex nop.est.by.sex <- Petersen::LP_est(nop.fit.sex.time, N=~-1+Sex) nop.est.by.sex$summary # Refer to vignettes for example using continuous variable (e.g. length) to model catchability
This will take a previous fit and return estimates of abundance after making various empirical adjustments
LP_est_adjust( N_hat, N_hat_SE, conf_level = 0.95, tag.retention.est = 1, tag.retention.se = 0, tag.reporting.est = 1, tag.reporting.se = 0, n1.adjust.est = 1, n1.adjust.se = 0, n2.adjust.est = 1, n2.adjust.se = 0, m2.adjust.est = 1, m2.adjust.se = 0, n.sim = 10000, trace = FALSE )LP_est_adjust( N_hat, N_hat_SE, conf_level = 0.95, tag.retention.est = 1, tag.retention.se = 0, tag.reporting.est = 1, tag.reporting.se = 0, n1.adjust.est = 1, n1.adjust.se = 0, n2.adjust.est = 1, n2.adjust.se = 0, m2.adjust.est = 1, m2.adjust.se = 0, n.sim = 10000, trace = FALSE )
N_hat |
Estimate of N that will be adjusted |
N_hat_SE |
SE of the N_hat |
conf_level |
The expected coverage for confidence intervals on N. |
tag.retention.est |
Estimated tag retention probability |
tag.retention.se |
Estimated SE of tag retention probability |
tag.reporting.est |
Estimated tag reporting probability |
tag.reporting.se |
Estimated SE of tag reporting probability |
n1.adjust.est |
Adjustment to "n1". This should typically be a ratio of new n1 to old n1 |
n1.adjust.se |
Adjustment to "n1" uncertainty |
n2.adjust.est |
Adjustment to "n2" This should typically be a ratio of new n2 to old n2 |
n2.adjust.se |
Adjustment to "n2" uncertainty |
m2.adjust.est |
Adjustment to "m2" This should typically be a ratio of new m2 to old m2 |
m2.adjust.se |
Adjustment to "m2" uncertainty |
n.sim |
Number of simulation runs to make |
trace |
If trace flag is set in call when estimating functions |
The estimate and SE are converted to a beta distribution for adjustment factors between 0 and 1 with equivalent mean and SD as the estimate and se. The estimate and se are used in normal distribution for adjustment factors for n1, n2, and m2. These adjustment factors are then simulated a large number of times and then multiplied together to get the mean and sd of all adjustments applied together. Then the abundance is simulated (on the log scale), the product taken, and the mean, sd, ci estimated directly.
An list object with a summary data frame and a data frame with the adjustment factors with the following objects summary A data frame with the adjusted abundance estimates, SE, and CI adjustment a data frame showing the adjustment factors applied for tag retention, tag reporting, n1 n2 or m2. datetime Date and time the adjustment was done
Schwarz, C. J. [email protected].
data(data_rodli) rodli.fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) rodli.est <- Petersen::LP_est(rodli.fit) res <- Petersen::LP_est_adjust(rodli.est$summary$N_hat, rodli.est$summary$N_hat_SE, tag.retention.est=.90, tag.retention.se=.05) res$summarydata(data_rodli) rodli.fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) rodli.est <- Petersen::LP_est(rodli.fit) res <- Petersen::LP_est_adjust(rodli.est$summary$N_hat, rodli.est$summary$N_hat_SE, tag.retention.est=.90, tag.retention.se=.05) res$summary
This will take a data frame of capture histories, frequencies, and additional covariates (e.g., strata and/or continuous covariates) and the model for the capture probabilities and will use conditional likelihood (Huggins, 1989) to fit the model. The population abundance is estimated using a Horvitz-Thompson type estimator and the user can request abundance estimates for sub-sets of the population.
LP_fit(data, p_model = ~..time, p_beta.start = NULL, trace = FALSE)LP_fit(data, p_model = ~..time, p_beta.start = NULL, trace = FALSE)
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
p_model |
Model for the captured probabilities. This can reference
other variables in the data frame, plus a special reserved term For some models (e.g., tag loss models), the |
p_beta.start |
Initial values for call to optimization routine for the beta parameters (on the logit scale). The values will be replicated to match the number of initial beta parameters needed. Some care is needed here! |
trace |
If trace flag is set in call when estimating functions |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of length 2.
10 Animals tagged but never seen again.
11 Animals tagged and recaptured and tag present at event 2.
01 Animals captured at event 2 that appear to be untagged.
An list object of class LP_fit with abundance estimates and other information with the following elements
summary A data frame with the model for the capture probabilities; the conditional log-likelihood; the number of parameters; the number of parameters, and method used to fit the model
data A data frame with the raw data used in the fit
fit Results of the fit from the optimizer
datetime Date and time the fit was done
After the fit is done, use the LP_est() function to get estimates of abundance.
Schwarz, C. J. [email protected].
Huggins, R. M. 1989. On the Statistical Analysis of Capture Experiments. Biometrika 76: 133–40.
# fit a simple Petersen model and get the estimated abundance data(data_rodli) fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) fit$summary # Now to get the estimated abundance est <- Petersen::LP_est(fit, N_hat=~1) est$summary # repeat the fit with the Chapman correction # we add an additional animal with history 11 rodli.chapman <- plyr::rbind.fill(data_rodli, data.frame(cap_hist="11", freq=1, comment="Added for Chapman")) rodli.chapman fit.chapman <- Petersen::LP_fit(data=rodli.chapman, p_model=~..time) fit.chapman$summary # Now to get the estimated abundance est.chapman <- Petersen::LP_est(fit.chapman, N_hat=~1) est.chapman$summary # Example of simple stratification (by sex) data(data_NorthernPike) nop.red <- plyr::ddply(data_NorthernPike, c("cap_hist","Sex"), plyr::summarize, freq=sum(freq)) nop.red # reduced capture history to speed execution time of example # Fit the various models nop.fit.sex.time <- Petersen::LP_fit(nop.red, p_model=~-1+Sex:..time) nop.fit.sex.time$summary # estimate of overall abundance nop.est.ALL <- Petersen::LP_est(nop.fit.sex.time, N=~1) nop.est.ALL$summary # estimate of abundance for each sex nop.est.by.sex <- Petersen::LP_est(nop.fit.sex.time, N=~-1+Sex) nop.est.by.sex$summary # Refer to vignettes for example using continuous variable (e.g. length) to model catchability# fit a simple Petersen model and get the estimated abundance data(data_rodli) fit <- Petersen::LP_fit(data=data_rodli, p_model=~..time) fit$summary # Now to get the estimated abundance est <- Petersen::LP_est(fit, N_hat=~1) est$summary # repeat the fit with the Chapman correction # we add an additional animal with history 11 rodli.chapman <- plyr::rbind.fill(data_rodli, data.frame(cap_hist="11", freq=1, comment="Added for Chapman")) rodli.chapman fit.chapman <- Petersen::LP_fit(data=rodli.chapman, p_model=~..time) fit.chapman$summary # Now to get the estimated abundance est.chapman <- Petersen::LP_est(fit.chapman, N_hat=~1) est.chapman$summary # Example of simple stratification (by sex) data(data_NorthernPike) nop.red <- plyr::ddply(data_NorthernPike, c("cap_hist","Sex"), plyr::summarize, freq=sum(freq)) nop.red # reduced capture history to speed execution time of example # Fit the various models nop.fit.sex.time <- Petersen::LP_fit(nop.red, p_model=~-1+Sex:..time) nop.fit.sex.time$summary # estimate of overall abundance nop.est.ALL <- Petersen::LP_est(nop.fit.sex.time, N=~1) nop.est.ALL$summary # estimate of abundance for each sex nop.est.by.sex <- Petersen::LP_est(nop.fit.sex.time, N=~-1+Sex) nop.est.by.sex$summary # Refer to vignettes for example using continuous variable (e.g. length) to model catchability
EXPERIMENTAL. This will take a data frame of capture histories, frequencies, and additional covariates (e.g., strata and/or continuous covariates) for a simple forward Petersen estimate plus estimates of escapement and associated stock proportions with SE for backwards estimation. DO NOT USE YET.
LP_for_rev_fit( data, E, E.SE, G, G.SE, min.G = 0.01, n.boot = 100, trace = FALSE )LP_for_rev_fit( data, E, E.SE, G, G.SE, min.G = 0.01, n.boot = 100, trace = FALSE )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
E |
Escapement at one or more terminal areas. E, E.SE, G, G.SE must all have the same length |
E.SE |
SE of the estimates of escapement |
G |
Estimated proportion of the stock at the first capture location estimated using GSI and other methods |
G.SE |
SE of the estimated stock proportion. |
min.G |
Miniumum acceptable stock proportion during the bootstrap estimation of uncertainty |
n.boot |
Number of bootstrap samples used to estimate the uncertainty |
trace |
Should intermediate tracing be enabled (e.g. browser() stops) |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of length 2.
10 Animals tagged but never seen again.
11 Animals tagged and recaptured and tag present at event 2.
01 Animals captured at event 2 that appear to be untagged.
A pseudo-likelihood is constructed consisting of the usual likelihood for a forward capture recapture and marginal likelihoods for each of the escapement (E) and stock proportions (G) point estimates. I have not integrated over the uncertainty in G and E.
An list object of class LP_for_rev_est with abundance estimates and measures of uncertainty
summary A data frame with the pseudo-likelihood value, abundance estimates and SE
data A data frame with the raw data used in the fit
fit Results of the fit from the optimizer
datetime Date and time the fit was done
Unlike other routine, it is not necessary to use a XX_est() function to get estimates of abundance.
Schwarz, C. J. [email protected].
# Example of combined forward and reverse MR # get some data n1 <- 500 n2 <- 1500 m2 <- 150 f.data <- data.frame(cap_hist=c("10","11","01"), freq=c(n1 - m2, m2, n2 - m2)) f.data E = 1500 E.SE = 150 G = .2 G.SE = .05 res <- LP_for_rev_fit(data=f.data, E=E, E.SE=E.SE, G=G, G.SE=G.SE)# Example of combined forward and reverse MR # get some data n1 <- 500 n2 <- 1500 m2 <- 150 f.data <- data.frame(cap_hist=c("10","11","01"), freq=c(n1 - m2, m2, n2 - m2)) f.data E = 1500 E.SE = 150 G = .2 G.SE = .05 res <- LP_for_rev_fit(data=f.data, E=E, E.SE=E.SE, G=G, G.SE=G.SE)
This will take a previous fit and return estimates of abundance. The population abundance is estimated using a Horvitz-Thompson type estimator and the user can request abundance estimates for sub-sets of the population
LP_IS_est(LP_IS_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)LP_IS_est(LP_IS_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)
LP_IS_fit |
A result of an LP_IS_fit() call. |
N_hat |
A formula requesting which abundance estimates should be formed. The formula are
expanded against the data frame to determine which records form part of the abundance estimate.
The formula is evaluated against the Some familiarity on how In addition to the variables in the |
conf_level |
The expected coverage for confidence intervals on N. |
trace |
If trace flag is set in call when estimating functions |
An list object with abundance estimates and other information with the following elements
summary Data frame with abundance estimates, their SE, and CIs as requested
detail List with many components, including the rawdata, model fitting information, observed and expected values, residual plot, etc
datetime Date and time the estimation was done from the fit.
Schwarz, C. J. [email protected].
data(data_wae_is_short) fit <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~..time) fit$summary est <- LP_IS_est(fit, N_hat=~1) est$summarydata(data_wae_is_short) fit <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~..time) fit$summary est <- LP_IS_est(fit, N_hat=~1) est$summary
In some LP studies, stratification is only done on a random sample of unmarked fish, e.g., only a sample of fish is sexed. Is is known as incomplete stratification. This is a wrapper to the published code for the case of stratification by a discrete covariate. At the moment, no other covariates are allowed, but see the published code.
LP_IS_fit( data, p_model, theta_model = ~-1 + ..time, lambda_model = ~-1 + ..cat, logit_p_offset = 0, logit_theta_offset = 0, logit_lambda_offset = 0, cat.unknown = "U", p_beta.start = NULL, trace = FALSE, control.optim = list(trace = 0, maxit = 1000) )LP_IS_fit( data, p_model, theta_model = ~-1 + ..time, lambda_model = ~-1 + ..cat, logit_p_offset = 0, logit_theta_offset = 0, logit_lambda_offset = 0, cat.unknown = "U", p_beta.start = NULL, trace = FALSE, control.optim = list(trace = 0, maxit = 1000) )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. At the moment, you are not allowed to use these covariates to used in the modeling process, but see the published code for more details. |
p_model |
Model for the captured probabilities. This can reference
other variables in the data frame, plus a special reserved term For some models (e.g., tag loss models), the |
theta_model |
Model for theta (sampling fraction). Usually, this is set to be different for the two sampling occasions, but you can constrain this to have equal sampling fractions at both occasions. |
lambda_model |
Model for lambda category proportions. Usually this is set to different for the categories
but you can constrain this with a null matrix and the |
logit_p_offset |
Used to fix capture probabilities at known values (seldom useful). Logit(p)=p_design %*% beta_p + logit_p_offset. |
logit_theta_offset |
Used to fix sampling fractions at known values (seldom useful). logit(theta) = theta_design %*% beta_theta + logit_theta_offset |
logit_lambda_offset |
Used to fix the sex ratio as a known value (e.g. .50) using logit(lambda) = lambda_design %*% beta_lambda + logit_lambda_offset. Set the design matrix to a matrix with all zeros. Notice that because the lambda proportions must sum to 1, only specify an offset matrix that is number of categories -1. |
cat.unknown |
Value of character used to indicate the unknown stratum in the capture histories. Currently, this is fixed to "U" regardless of what is specified. |
p_beta.start |
Initial values for call to optimization routine for the beta parameters (on the logit scale). The values will be replicated to match the number of initial beta parameters needed. Some care is needed here! |
trace |
If trace flag is set in call when estimating functions |
control.optim |
Control values passed to optim() optimizer. |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of length 2.
The strata values are single character values with "U" typically representing a fish not measured
for the stratification variable. For example, consider the case where only a sample of unmarked fish
are examined for sex (M or F). Possible capture histories are:
M0 Animals tagged and sexed as male but never seen again.
MM Animals tagged and sexed as male and recaptured and tag present at event 2.
0M Animals captured at event 2 that appears to be untagged and was sexed as male.
F0 Animals tagged and sexed as female but never seen again.
FF Animals tagged and sexed as female and recaptured and tag present at event 2.
0F Animals captured at event 2 that appears to be untagged and was sexed as female.
U0 Animals tagged and not sexed but never seen again.
UU Animals tagged and not sexed and recaptured and tag present at event 2.
0U Animals captured at event 2 that appears to be untagged and was not sexed.
Capture histories such as UF or UM are not allowed since only UNTAGGED animals are examined and sexed. Similarly, capture histories such as FM or MF are not allowed.
An list object of class LP_IS_fit with abundance estimates and other information with the following elements
summary A data frame with the model for the capture probabilities, the sampling fractions at each capture occasion, and the category proportions; the conditional log-likelihood; the number of parameters; the number of parameters, and method used to fit the model
data A data frame with the raw data used in the fit
fit Results of the fit including the estimates, SE, vcov, etc.
fit.call Arguments used in the fit
datetime Date and time the fit was done
Schwarz, C. J. [email protected].
Premarathna, W.A.L., Schwarz, C.J., Jones, T.S. (2018) Partial stratification in two-sample capture–recapture experiments. Environmetrics, 29:e2498. doi:10.1002/env.2498
data(data_wae_is_short) fit <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~..time) fit$summary est <- LP_IS_est(fit, N_hat=~1) est$summarydata(data_wae_is_short) fit <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~..time) fit$summary est <- LP_IS_est(fit, N_hat=~1) est$summary
Print the results from a fit a Lincoln-Petersen Model with incomplete stratification
LP_IS_print(IS.results)LP_IS_print(IS.results)
IS.results |
Results from fitting an incomplete stratification model |
A nicely formatted report showing the results of the fit.
Model information (summary of arguments, model name, negative log-likelihood, number of parameters, AICc)
Raw data used in the fit (history, frequency,categories)
Initial values used in the optimization of the likelihood for the parameters
Design matrix and offset values for the parameters
Maximum likelihood estimates for the parameters and estimated abundance by category
SE for the above
Observed and expected counts for each capture history
Residual plot constructed from the previous observed and expected counts
data(data_wae_is_short) res <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~-1 + ..cat:..time) LP_IS_print(res)data(data_wae_is_short) res <- Petersen::LP_IS_fit(data=data_wae_is_short, p_model=~-1 + ..cat:..time) LP_IS_print(res)
This will take a series of LP fits and computes the model averages for each set of N_hat
LP_modavg(..., N_hat = ~1, conf_level = 0.95)LP_modavg(..., N_hat = ~1, conf_level = 0.95)
... |
Series of LP fits |
N_hat |
A formula requesting which abundance estimates should be formed. The formula are
expanded against the data frame to determine which records form part of the abundance estimate.
The formula is evaluated against the Some familiarity on how In addition to the variables in the |
conf_level |
The expected coverage for confidence intervals on N. |
An data frame with model averaged values for abundance
data(data_rodli) mt <- Petersen::LP_fit(data=data_rodli, p_model=~..time) m0 <- Petersen::LP_fit(data=data_rodli, p_model=~1) Petersen::LP_modavg(m0,mt)data(data_rodli) mt <- Petersen::LP_fit(data=data_rodli, p_model=~..time) m0 <- Petersen::LP_fit(data=data_rodli, p_model=~1) Petersen::LP_modavg(m0,mt)
This will take a previous fit and return estimates of abundance.
LP_SPAS_est(LP_SPAS_fit, conf_level = 0.95, trace = FALSE)LP_SPAS_est(LP_SPAS_fit, conf_level = 0.95, trace = FALSE)
LP_SPAS_fit |
A result of an call to fitting at SPAS object. |
conf_level |
The expected coverage for confidence intervals on N. |
trace |
If trace flag is set in call when estimating functions |
An list object with abundance estimates and other information with the following elements
summary Data frame with abundance estimates, their SE, and CIs as requested
datetime Date and time the estimation was done from the fit.
Schwarz, C. J. [email protected].
data(data_spas_harrison) fit <- Petersen::LP_SPAS_fit(data=data_spas_harrison, model.id="Pooling rows 5/6", row.pool.in=c(1,2,3,4,56,56), col.pool.in=c(1,2,3,4,5,6)) fit$summary est <- Petersen::LP_SPAS_est(fit) est$summarydata(data_spas_harrison) fit <- Petersen::LP_SPAS_fit(data=data_spas_harrison, model.id="Pooling rows 5/6", row.pool.in=c(1,2,3,4,56,56), col.pool.in=c(1,2,3,4,5,6)) fit$summary est <- Petersen::LP_SPAS_est(fit) est$summary
This function is a wrapper to fits a SPAS model(Schwarz, 2023; Schwarz and Taylor, 1998). Consult the SPAS package for more details.
LP_SPAS_fit( data, model.id = "Base model", autopool = FALSE, row.pool.in = NULL, col.pool.in = NULL, min.released = 100, min.inspected = 50, min.recaps = 50, min.rows = 1, min.cols = 1, quietly = FALSE )LP_SPAS_fit( data, model.id = "Base model", autopool = FALSE, row.pool.in = NULL, col.pool.in = NULL, min.released = 100, min.inspected = 50, min.recaps = 50, min.rows = 1, min.cols = 1, quietly = FALSE )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
model.id |
Character string identifying the name of the model. |
autopool |
Should the automatic pooling algorithms be used. Give more details here on these rule work. |
row.pool.in, col.pool.in
|
Vectors (character/numeric) of length s and t respectively. These identify the rows/columns to be pooled before the analysis is done. The vectors consists of entries where pooling takes place if the entries are the same. For example, if s=4, then row.pool.in = c(1,2,3,4) implies no pooling because all entries are distinct; row.pool.in=c("a","a","b","b") implies that the first two rows will be pooled and the last two rows will be pooled. It is not necessary that row/columns be continuous to be pooled, but this is seldom sensible. A careful choice of pooling labels helps to remember what as done, e.g. row.pool.in=c("123","123","123","4") indicates that the first 3 rows are pooled and the 4th row is not pooled. Character entries ensure that the resulting matrix is sorted properly (e.g. if row.pool.in=c(123,123,123,4), then the same pooling is done, but the matrix rows are sorted rather strangely. |
min.released |
Minimum number of releases in a pooled row |
min.inspected |
Minimum number of inspections in a pooled column |
min.recaps |
Minimum number of recaptures before any rows can be pooled |
min.rows, min.cols
|
Minimum number or rows and columns after pooling |
quietly |
Suppress all console messages that occur during the fit. This includes the progress bar when a model that requires MCMC is fit (LP_BTSPAS_fit_Diag and LP_BTSPAS_fit_NonDiag), or a trace of the likelihood during the fit (LP_SPAS_fit). |
An list object of class LP_SPAS_fit with abundance estimates and other information with the following elements
summary A data frame with the model for the capture probabilities; the conditional log-likelihood; the number of parameters; the number of parameters, condition factor of the data matrix, and method used to fit the model
data A data frame with the raw data used in the fit
fit Results of the fit including the estimates, SE, vcov, etc.
row.pool.in, col.pool.in, autopool Arguments used in the fit to indicate row, column, or automatic pooling used in the fit.
datetime Date and time the fit was done
After the fit is complete, use the LP_SPAS_est() function to extract the estimates, and the SPAS::SPAS.print.model() function to get a nicely formatted report on the fit.
Schwarz CJ (2023). SPAS: Stratified-Petersen Analysis System. R package version 2023.3.31, https://CRAN.R-project.org/package=SPAS.
Schwarz, C. J. and Taylor, C. G. (1998). The use of the stratified-Petersen estimator in fisheries management: estimating the number of pink salmon (Oncorhynchus gorbuscha) that spawn in the Fraser River. Canadian Journal of Fisheries and Aquatic Sciences 55, 281-297. https://doi.org/10.1139/f97-238
data(data_spas_harrison) fit <- Petersen::LP_SPAS_fit(data=data_spas_harrison, model.id="Pooling rows 5/6", row.pool.in=c(1,2,3,4,56,56), col.pool.in=c(1,2,3,4,5,6),quietly=TRUE) fit$summary est <- Petersen::LP_SPAS_est(fit) est$summary # make a nice report using the SPAS package functions SPAS::SPAS.print.model(fit$fit)data(data_spas_harrison) fit <- Petersen::LP_SPAS_fit(data=data_spas_harrison, model.id="Pooling rows 5/6", row.pool.in=c(1,2,3,4,56,56), col.pool.in=c(1,2,3,4,5,6),quietly=TRUE) fit$summary est <- Petersen::LP_SPAS_est(fit) est$summary # make a nice report using the SPAS package functions SPAS::SPAS.print.model(fit$fit)
This function takes the capture histories and computes $n_1$, $n_2$ and $m_2$.
LP_summary_stats(data)LP_summary_stats(data)
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
Summary statistics of n1 (number observed at first occasion), n2 (number observed at second occasion), and m2 number recaptured in second occasion.
data(data_rodli) LP_summary_stats(data_rodli)data(data_rodli) LP_summary_stats(data_rodli)
This function takes the capture histories and stratification variable and computes the test for equal marked fractions.
LP_test_equal_mf(data, strat_var, do.fisher.test = FALSE)LP_test_equal_mf(data, strat_var, do.fisher.test = FALSE)
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
strat_var |
Variable in the dataframe that serves as a stratification variable for contingency table tests of equal marked fraction or equal recapture probability |
do.fisher.test |
Do a fisher test? |
List containing the contingency table and the chi-square test and fisher-exact test
data(data_NorthernPike) LP_test_equal_mf(data_NorthernPike, "Sex")data(data_NorthernPike) LP_test_equal_mf(data_NorthernPike, "Sex")
This function takes the capture histories and stratification variable and computes the test for equal recapture probabilities.
LP_test_equal_recap(data, strat_var, do.fisher.test = FALSE)LP_test_equal_recap(data, strat_var, do.fisher.test = FALSE)
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
strat_var |
Variable in the dataframe that serves as a stratification variable for contingency table tests of equal marked fraction or equal recapture probability |
do.fisher.test |
Should a fisher exact test be done? |
List containing the contingency table and the chi-square test and fisher-exact test
data(data_NorthernPike) LP_test_equal_recap(data_NorthernPike, "Sex")data(data_NorthernPike) LP_test_equal_recap(data_NorthernPike, "Sex")
This will take a previous fit and return estimates of abundance. The population abundance is estimated using a Horvitz-Thompson type estimator based only on p1 and the user can request abundance estimates for sub-sets of the population.
LP_TL_est(LP_TL_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)LP_TL_est(LP_TL_fit, N_hat = ~1, conf_level = 0.95, trace = FALSE)
LP_TL_fit |
A result of an LP_TL_fit() call. |
N_hat |
A formula requesting which abundance estimates should be formed. The formula are
expanded against the data frame to determine which records form part of the abundance estimate.
The formula is evaluated against the Some familiarity on how In addition to the variables in the |
conf_level |
The expected coverage for confidence intervals on N. |
trace |
If trace flag is set in call when estimating functions |
An list object with abundance estimates and other information with the following elements
summary Data frame with abundance estimates, their SE, and CIs as requested
detail List with many components, including the rawdata, model fitting information, etc
datetime Date and time the estimation was done from the fit.
Schwarz, C. J. [email protected].
data(data_kokanee_tagloss) fit <- Petersen::LP_TL_fit(data=data_kokanee_tagloss, p_model=~1, rho_model=~1, dt_type="notD") fit$summary est <- Petersen::LP_TL_est(fit, N_hat=~1) est$summarydata(data_kokanee_tagloss) fit <- Petersen::LP_TL_fit(data=data_kokanee_tagloss, p_model=~1, rho_model=~1, dt_type="notD") fit$summary est <- Petersen::LP_TL_est(fit, N_hat=~1) est$summary
This will take a data frame of capture histories, frequencies, and additional covariates (e.g., strata and/or continuous covariates) and the model for p1 and the tag retention probabilities and will use conditional likelihood (conditional on capture at time 2) to fit the model. The population abundance is estimated using a Horvitz-Thompson type estimator and the user can request abundance estimates for sub-sets of the population. Refer to references and appendices in vignettes for more details.
LP_TL_fit( data, dt_type = NULL, p_model, rho_model, all_beta.start = NULL, trace = FALSE )LP_TL_fit( data, dt_type = NULL, p_model, rho_model, all_beta.start = NULL, trace = FALSE )
data |
Data frame containing the variables:
plus any other covariates (e.g. discrete strata and/or continuous covariates) to be used in the model fitting. |
dt_type |
Double Tag type. Valid values are
|
p_model |
Model for the captured probabilities. This can reference
other variables in the data frame, plus a special reserved term For some models (e.g., tag loss models), the |
rho_model |
Model for retention probabilities |
all_beta.start |
Initial values for call to optimization routine for the beta parameters (on the logit scale). The values will be replicated to match the number of initial beta parameters needed. Some care is needed here since the parameter order are for the p1 probabilities and then for the rho probabilities |
trace |
If trace flag is set in call when estimating functions |
The frequency variable (freq in the data argument) is the number of animals with the corresponding capture history.
Capture histories (cap_hist in the data argument) are character values of length 4.
If the tag loss model is two indistinguishable tags (dt_type="notD"), then valid capture histories are:
1100 Animals double tagged but never seen again.
111X Animals double tagged, but only 1 tag was present when animal recaptured at second event.
1111 Animals double tagged and both tags present when animal recaptured at second event.
1000 Animals single tagged and never seen again.
0100 Animals single tagged and never seen again.
1010 Animals single tagged and recaptured with the single tag.
0101 Animals single tagged and recaptured with the single tag.
0010 Animals APPARENTLY captured for the first time at event 2. This includes animals that are newly captured, plus fish that were tagged and lost all their tags, and were captured again
If the tag loss model is two distinguishable tags (dt_type="twoD"), then valid capture histories are the same
as above except the history 111X is replaced by:
1110 Animals double tagged, but only the first of the double tags applied was present when animal recaptured at event 2,
1101 Animals double tagged, but only the second of the double tags applied was present when animal recaptured at event 2.
If the second tag is a permanent batch mark (dt_type="t2perm"), then valid capture histories are:
1P00 Animals double tagged but never seen again.
1P0P Animals double tagged,but non-permanent tag missing when animal recaptured at second event.
1P1P Animals double tagged and both tags present when animal recaptured at second event.
1000 Animals single tagged and never seen again.
0P00 Animals single tagged with a permanent batch mark only and never seen again.
1010 Animals single tagged and recaptured with the single tag.
0P0P Animals single tagged with the permanent batch mark and recaptured with the permanent tag.
0010 Animals APPARENTLY captured for the first time at event 2. This includes animals that are newly captured, plus fish that were tagged and lost all their tags, and were captured again
An list object of class LP_TL_fit-notD or LP_TL_fit-twoD, or LP_TL_fit-t2per (depending on the type of double tag) with abundance estimates and other information with the following elements
summary A data frame with the model for the capture probabilities, and tag retention probabilities; the conditional log-likelihood; the number of parameters; the number of parameters, and method used to fit the model
data A data frame with the raw data used in the fit
fit Results of the fit including the estimates, SE, vcov, etc.
datetime Date and time the fit was done
After the fit is complete, use the LP_TL_est() function to obtain estimates.
Schwarz, C. J. [email protected].
Seber, G. A. F., and R. Felton. (1981). Tag Loss and the Petersen Mark-Recapture Experiment. Biometrika 68, 211–19.
Hyun, S.-Y., Reynolds.J.H., and Galbreath, P.F. (2012). Accounting for Tag Loss and Its Uncertainty in a Mark–Recapture Study with a Mixture of Single and Double Tags. Transactions of the American Fisheries Society, 141, 11-25 http://dx.doi.org/10.1080/00028487.2011.639263
data(data_kokanee_tagloss) fit <- Petersen::LP_TL_fit(data=data_kokanee_tagloss, p_model=~1, rho_model=~1, dt_type="notD") fit$summary est <- Petersen::LP_TL_est(fit, N_hat=~1) est$summarydata(data_kokanee_tagloss) fit <- Petersen::LP_TL_fit(data=data_kokanee_tagloss, p_model=~1, rho_model=~1, dt_type="notD") fit$summary est <- Petersen::LP_TL_est(fit, N_hat=~1) est$summary
This function creates simulated capture histories for the Lincoln-Petersen model with tag loss.
LP_TL_simulate( dt_type = NULL, N = 1000, cov1 = function(N) { rep(1, N) }, cov2 = function(cov1) { rep(1, length(cov1)) }, p1 = function(cov1, cov2) { rep(0.1, length(cov1)) }, pST = function(cov1, cov2) { rep(0.5, length(cov1)) }, pST.1 = function(cov1, cov2) { rep(1, length(cov1)) }, rho1 = function(cov1, cov2) { rep(0.8, length(cov1)) }, rho2 = function(cov1, cov2) { rep(0.8, length(cov1)) }, p2 = function(cov1, cov2) { rep(0.1, length(cov1)) }, seed = round(1e+08 * runif(1)), trace = FALSE )LP_TL_simulate( dt_type = NULL, N = 1000, cov1 = function(N) { rep(1, N) }, cov2 = function(cov1) { rep(1, length(cov1)) }, p1 = function(cov1, cov2) { rep(0.1, length(cov1)) }, pST = function(cov1, cov2) { rep(0.5, length(cov1)) }, pST.1 = function(cov1, cov2) { rep(1, length(cov1)) }, rho1 = function(cov1, cov2) { rep(0.8, length(cov1)) }, rho2 = function(cov1, cov2) { rep(0.8, length(cov1)) }, p2 = function(cov1, cov2) { rep(0.1, length(cov1)) }, seed = round(1e+08 * runif(1)), trace = FALSE )
dt_type |
Double Tag type. Valid values are
|
N |
Population size |
cov1 |
Function to generate first covariate for each member of population as function of |
cov2 |
Function to generate second covariate for each member of population as function of |
p1 |
Function to generate P(capture) at event 1 for each member of population as function of |
pST |
Function to generate P(single tag) if captured at event 1 as function of |
pST.1 |
Function to generate p(apply single tag to first position at event 1) as function of |
rho1 |
Function to generate P(tag1 retained) as function of |
rho2 |
Function to generate P(tag2 retained) as function of |
p2 |
Function to generate P(capture) at event 2 for each member of population as function of |
seed |
Initial value of random seed |
trace |
Trace flag to help debug if things fail. |
The cov1 function takes the value N and returns N covariate values. For example these could be
simulated length, or sex of each fish. The cov2 function takes the cov1 values and generates
a second covariate. Two covariates should be sufficient for most capture-recapture simulations.
If generating continuous covariates, you should round the covariate to
about 100 distinct values to speed up your simulation.
The remaining functions take the two covariate values and generate capture probabilities, single tag probabilities, placing tags on fish, and tag retention probabilities. These should all be in the range of 0 to 1.
After generating capture histories for the entire population, animals never seen are "discarded" and the data set is compress to unique combinations of the two covariates and the capture history with the frequency variable set accordingly.
Data frame with observed capture histories
sim_data <-LP_TL_simulate( dt_type="t2perm", # permanent tag N=1000, cov1=function(N) {rep(1,N)}, cov2=function(cov1) {rep(1, length(cov1))}, p1 =function(cov1, cov2){rep(.1, length(cov1))}, pST =function(cov1, cov2){rep(.25,length(cov1))}, rho1=function(cov1, cov2){rep(.70,length(cov1))}, rho2=function(cov1, cov2){rep(1, length(cov1))}, # permanent second tag p2 =function(cov1, cov2){rep(.1, length(cov1))}, seed=round(1000000*runif(1))) sim_datasim_data <-LP_TL_simulate( dt_type="t2perm", # permanent tag N=1000, cov1=function(N) {rep(1,N)}, cov2=function(cov1) {rep(1, length(cov1))}, p1 =function(cov1, cov2){rep(.1, length(cov1))}, pST =function(cov1, cov2){rep(.25,length(cov1))}, rho1=function(cov1, cov2){rep(.70,length(cov1))}, rho2=function(cov1, cov2){rep(1, length(cov1))}, # permanent second tag p2 =function(cov1, cov2){rep(.1, length(cov1))}, seed=round(1000000*runif(1))) sim_data
Split a vector of capture histories into a matrix with one column for each occasion
split_cap_hist(cap_hist, sep = "", n = 2, prefix = "t", make.numeric = FALSE)split_cap_hist(cap_hist, sep = "", n = 2, prefix = "t", make.numeric = FALSE)
cap_hist |
A vector of capture histories. |
sep |
What separates the individual history values |
n |
Number of sampling events in each history |
prefix |
Prefix for labeling columns of matrix |
make.numeric |
Change the expanded columns to numeric from character? |
@template data.cap_hist
A matrix of capture histories with 1 column per sampling event
# standard 2 character capture histor data(data_rodli) Petersen::split_cap_hist(data_rodli$cap_hist) # history vector with ".." separating the fields test <- c("1..1","1..0") split_cap_hist(test, sep=stringr::fixed(".."))# standard 2 character capture histor data(data_rodli) Petersen::split_cap_hist(data_rodli$cap_hist) # history vector with ".." separating the fields test <- c("1..1","1..0") split_cap_hist(test, sep=stringr::fixed(".."))