Package 'modesto'

Title: Modeling and Analysis of Stochastic Systems
Description: Compute important quantities when we consider stochastic systems that are observed continuously. Such as, Cost model, Limiting distribution, Transition matrix, Transition distribution and Occupancy matrix. The methods are described, for example, Ross S. (2014), Introduction to Probability Models. Eleven Edition. Academic Press.
Authors: Carlos Alberto Cardozo Delgado
Maintainer: Carlos Alberto Cardozo Delgado <[email protected]>
License: GPL-3
Version: 0.1.4
Built: 2024-11-12 06:42:32 UTC
Source: CRAN

Help Index


Tool to computate the Expected Total Cost vector for a Continuous Time Markov Chain, CTMC.

Description

ETCt is used to obtain the Expected Total Cost vector up to t of a homogeneous continuous time Markov chain.

Usage

ETCt(R, c, t, epsilon = 0.001)

Arguments

R

numeric, represents the rate matrix of a CTMC.

c

vector, represents the costs of the states of a CTMC.

t

numeric, represents the length of time.

epsilon

numeric, represents the error bound of the approximation of M(t). Default value is 0.001.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.

Examples

library(modesto)
# A four states CTMC example
R <- matrix(c(0,1,0,0,0, 1/72,0,1,0,0, 0,2/72,0,1,0, 0,0,3/72,0,1/2, 0,0,0,4/72,0),5,5,byrow=TRUE)
ETCt(R,c(-80,-15,50,125,200),t=24,epsilon=0.001)

Tool to computate the limiting distribution for a Continuous Time Markov Chain, CTMC.

Description

LimDist is used to obtain the limiting distribution of a homogeneous continuous time Markov chain.

Usage

LimDist(X, rate, epsilon = 0.01, iter)

Arguments

X

matrix, represents a rate matrix of a CTMC or the transition probability matrix of the DTMC associated to the CTMC.

rate

boolean, if rate is equal to TRUE then the argument X represents the rate matrix of the CTMC. If rate is equal to FALSE then the argument X represents the probability transition matrix of the CTMC.

epsilon

numeric, represents the error of approximation.

iter

integer, represents the maximum of iterations.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.


Tool to computate the Long-Run Cost Rate for a Continuous Time Markov Chain, CTMC.

Description

LRC is used to obtain the Long-Run Cost Rate of a homogeneous continuous time Markov chain.

Usage

LRC(X, costs)

Arguments

X

matrix, represents the rate matrix of a CTMC.

costs

vector, represents the costs of the states of a CTMC.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.

Examples

## Not run: library(modesto)
# A five states CTMC example
R <- matrix(c(0,1,0,0,0, 1/72,0,1,0,0, 0,2/72,0,1,0, 0,0,3/72,0,1/2, 0,0,0,4/72,0),5,5,byrow=TRUE)
LRC(X=R,costs=c(-80,-15,50,125,200))

## End(Not run)

Tool to computate the Occupancy Matrix for a Continuous Time Markov Chain, CTMC.

Description

Mt is used to obtain the Occupancy matrix of a homogeneous continuous time Markov chain for a period of time [0,t].

Usage

Mt(R, t, epsilon = 0.001)

Arguments

R

numeric, represents the rate matrix of a CTMC.

t

numeric, represents the length of time.

epsilon

numeric, represents the error bound of the approximation of M(t). Default value is 0.001.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.

Examples

library(modesto)
# A five states CTMC example
R <- matrix(c(0,1,0,0,0, 1/72,0,1,0,0, 0,2/72,0,1,0, 0,0,3/72,0,1/2, 0,0,0,4/72,0),5,5,byrow=TRUE)
Mt(R,t=24,epsilon=0.005)

Tool to computate the transition matrix for a Continuous Time Markov Chain, CTMC.

Description

Pt2 is used to obtain the transition matrix of a homogeneous continuous time Markov chain for a period of time of t.

Usage

Pt2(R, t, epsilon = 0.001)

Arguments

R

numeric, represents the rate matrix of a CTMC.

t

numeric, represents the length of time.

epsilon

numeric, represents the error bound of the approximation of P(t). Default values is 0.001.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.

Examples

library(modesto)
# A two states CTMC example
Pt2(matrix(c(0,2,3,0),2,2,byrow=TRUE),t=0.7,epsilon=0.005)
# A four states CTMC example
R <- matrix(c(0,2,3,0,4,0,2,0,0,2,0,2,1,0,3,0),4,4,byrow=TRUE)
Pt2(R,t=0.7,epsilon=0.005)
# require(microbenchmark)
# microbenchmark(Pt(R,t=0.7,epsilon=0.005),Pt2(R,t=0.7,epsilon=0.005),times=1000L)

Tool to computate the transient probability distribution for a Continuous Time Markov Chain, CTMC.

Description

Pt is used to obtain the transient probability distribution of a homogeneous continuous time Markov chain at a point of time t.

Usage

PXt(X0, R, t, epsilon = 0.001)

Arguments

X0

numeric vector, represents the probability distribution of the initial state.

R

numeric, represents the rate matrix of a CTMC.

t

numeric, represents the length of time.

epsilon

numeric, represents the error bound of the approximation of P(t). Default values is 0.001.

Author(s)

Carlos Alberto Cardozo Delgado <[email protected]>.

References

Ross, S, Introduction to Probability Models, Eleven Edition. Academic Press, 2014.

Kulkarni V, Introduction to modeling and analysis of stochastic systems. Second Edition. Springer-Verlag, 2011.

Examples

library(modesto)
# A three states CTMC example
R <- matrix(c(0,2,0,3,0,1,0,6,0),3,3,byrow=TRUE)
X0 <- c(1,0,0)
PXt(X0,R,t=0.5,epsilon=0.005)
X0 <- c(0,0,1)
PXt(X0,R,t=0.5,epsilon=0.005)

summary.modesto

Description

summary.modesto displays the summary of calculated quantities from an object of class 'modesto'.

Usage

## S3 method for class 'modesto'
summary(object, ...)

Arguments

object

an object of the class 'modesto'. This object is returned from the call to LimDist() function.

...

other arguments.

Examples

# A two states CTMC example
model <-LimDist(matrix(c(0,2,3,0),2,2,byrow=TRUE),rate=TRUE,epsilon=0.005)
summary(model)