R/main.R
In saemixdevelopment/saemix: Stochastic Approximation Expectation Maximization (SAEM) Algorithm
Defines functions
saemix
Documented in
saemix
#' Stochastic Approximation Expectation Maximization (SAEM) algorithm
#'
#' SAEM algorithm perform parameter estimation for nonlinear mixed effects
#' models without any approximation of the model (linearization, quadrature
#' approximation, . . . )
#'
#' The SAEM algorithm is a stochastic approximation version of the standard EM
#' algorithm proposed by Kuhn and Lavielle (see reference). Details of the
#' algorithm can be found in the pdf file accompanying the package.
#'
#' @name saemix
#' @aliases initialiseMainAlgo mstep estep
#'
#' @param model an object of class SaemixModel, created by a call to the
#' function \code{\link{saemixModel}}
#' @param data an object of class SaemixData, created by a call to the function
#' \code{\link{saemixData}}
#' @param control a list of options, see \code{\link{saemixControl}}
#' @return An object of class SaemixObject containing the results of the fit of
#' the data by the non-linear mixed effect model. A summary of the results is
#' printed out to the terminal, and, provided the appropriate options have not
#' been changed, numerical and graphical outputs are saved in a directory.
#' @author Emmanuelle Comets <emmanuelle.comets@@inserm.fr>, Audrey Lavenu,
#' Marc Lavielle.
#' @seealso \code{\link{SaemixData}},\code{\link{SaemixModel}},
#' \code{\link{SaemixObject}}, \code{\link{saemixControl}},
#' \code{\link{plot.saemix}}
#' @references Comets E, Lavenu A, Lavielle M. Parameter estimation in nonlinear mixed effect models using saemix, an R implementation of the SAEM algorithm. Journal of Statistical Software 80, 3 (2017), 1-41.
#'
#' Kuhn E, Lavielle M. Maximum likelihood estimation in nonlinear mixed effects models. Computational Statistics and Data Analysis 49, 4 (2005), 1020-1038.
#'
#' Comets E, Lavenu A, Lavielle M. SAEMIX, an R version of the SAEM algorithm.
#' 20th meeting of the Population Approach Group in Europe, Athens, Greece
#' (2011), Abstr 2173.
#' @keywords models
#' @examples
#'
#' data(theo.saemix)
#'
#' saemix.data<-saemixData(name.data=theo.saemix,header=TRUE,sep=" ",na=NA,
#' name.group=c("Id"),name.predictors=c("Dose","Time"),
#' name.response=c("Concentration"),name.covariates=c("Weight","Sex"),
#' units=list(x="hr",y="mg/L", covariates=c("kg","-")), name.X="Time")
#'
#' model1cpt<-function(psi,id,xidep) {
#' dose<-xidep[,1]
#' tim<-xidep[,2]
#' ka<-psi[id,1]
#' V<-psi[id,2]
#' CL<-psi[id,3]
#' k<-CL/V
#' ypred<-dose*ka/(V*(ka-k))*(exp(-k*tim)-exp(-ka*tim))
#' return(ypred)
#' }
#'
#' saemix.model<-saemixModel(model=model1cpt,
#' description="One-compartment model with first-order absorption",
#' psi0=matrix(c(1.,20,0.5,0.1,0,-0.01),ncol=3, byrow=TRUE,
#' dimnames=list(NULL, c("ka","V","CL"))),transform.par=c(1,1,1),
#' covariate.model=matrix(c(0,1,0,0,0,0),ncol=3,byrow=TRUE),fixed.estim=c(1,1,1),
#' covariance.model=matrix(c(1,0,0,0,1,0,0,0,1),ncol=3,byrow=TRUE),
#' omega.init=matrix(c(1,0,0,0,1,0,0,0,1),ncol=3,byrow=TRUE),error.model="constant")
#'
#'
#' # Not run (strict time constraints for CRAN)
#' # saemix.fit<-saemix(saemix.model,saemix.data,list(seed=632545,directory="newtheo",
#' # save=FALSE,save.graphs=FALSE))
#'
#' # Prints a summary of the results
#' # print(saemix.fit)
#'
#' # Outputs the estimates of individual parameters
#' # psi(saemix.fit)
#'
#' # Shows some diagnostic plots to evaluate the fit
#' # plot(saemix.fit)
#'
#'
#' @export saemix
saemix<-function(model,data,control=list()) {
# Convergence plots during fit (special function, not user-level)
convplot.infit<-function(allpar,K1,niter=0) {
# Convergence plots for all the fixed effects, random effects and residual variability
np<-dim(allpar)[2]
K<-dim(allpar)[1]
n1<-round(sqrt(np))
n2<-ceiling(np/n1)
if(n1>5 | n2>5) {n1<-3;n2<-4}
if(niter==0) niter<-K
par(mfrow=c(n1,n2))
for(j in 1:np) {
plot(1:niter,allpar[1:niter,j],type="l", xlab="Iteration", ylab=colnames(allpar)[j])
abline(v=K1)
}
}
if(!is(model,"SaemixModel")) {
cat("Please provide a valid model object (see the help page for SaemixModel)\n")
return()
}
if(!is(data,"SaemixData")) {
cat("Please provide a valid data object (see the help page for SaemixData)\n")
return()
}
saemixObject<-new(Class="SaemixObject",data=data,model=model,options=control)
# saemixObject<-new(Class="SaemixObject",data=saemix.data, model=saemix.model,options=saemix.options)
opt.warn<-getOption("warn")
if(!saemixObject["options"]$warnings) options(warn=-1)
saemix.options<-saemixObject["options"]
saemix.model<-saemixObject["model"]
saemix.data<-saemixObject["data"]
saemix.data@ocov<-saemix.data@ocov[saemix.data@data[,"mdv"]==0,,drop=FALSE]
saemix.data@data<-saemix.data@data[saemix.data@data[,"mdv"]==0,]
saemix.data@ntot.obs<-dim(saemix.data@data)[1]
# showall(saemixObject)
# Initialising random generator
OLDRAND<-TRUE
set.seed(saemix.options$seed)
############################################
# Main Algorithm
############################################
# Initialisation - creating several lists with necessary information extracted (Uargs, Dargs, opt,varList, suffStat)
xinit<-initialiseMainAlgo(saemix.data,saemix.model,saemix.options)
saemix.model<-xinit$saemix.model
Dargs<-xinit$Dargs
Uargs<-xinit$Uargs
varList<-xinit$varList
phiM<-xinit$phiM
mean.phi<-xinit$mean.phi
DYF<-xinit$DYF
opt<-xinit$opt
betas<-betas.ini<-xinit$betas
fixed.psi<-xinit$fixedpsi.ini
var.eta<-varList$diag.omega
theta0<-c(fixed.psi,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
parpop<-matrix(data=0,nrow=(saemix.options$nbiter.tot+1),ncol=(Uargs$nb.parameters+length(Uargs$i1.omega2)+length(saemix.model["indx.res"])))
colnames(parpop)<-c(saemix.model["name.modpar"], saemix.model["name.random"], saemix.model["name.sigma"][saemix.model["indx.res"]])
allpar<-matrix(data=0,nrow=(saemix.options$nbiter.tot+1), ncol=(Uargs$nb.betas+length(Uargs$i1.omega2)+length(saemix.model["indx.res"])))
colnames(allpar)<-c(saemix.model["name.fixed"],saemix.model["name.random"], saemix.model["name.sigma"][saemix.model["indx.res"]])
parpop[1,]<-theta0
allpar[1,]<-xinit$allpar0
# using several Markov chains - only useful if passed back to main routine...
# chdat<-new(Class="SaemixRepData",data=saemix.data, nb.chains=saemix.options$nb.chains)
# NM<-chdat["NM"]
# IdM<-chdat["dataM"]$IdM
# yM<-chdat["dataM"]$yM
# XM<-chdat["dataM"][,saemix.data["name.predictors"],drop=FALSE]
# List of sufficient statistics - change during call to stochasticApprox
suffStat<-list(statphi1=0,statphi2=0,statphi3=0,statrese=0)
phi<-array(data=0,dim=c(Dargs$N, Uargs$nb.parameters, saemix.options$nb.chains))
# structural model, check nb of parameters
structural.model<-saemix.model["model"]
# nb.parameters<-saemix.model["nb.parameters"]
# Running the algorithm
# hw=waitbar(1,'Estimating the population parameters (SAEM). Wait...');
if(saemix.options$displayProgress) par(ask=FALSE)
cat("Running main SAEM algorithm\n")
print(date())
for (kiter in 1:saemix.options$nbiter.tot) { # Iterative portion of algorithm
# SAEM convergence plots
if(kiter%%saemix.options$nbdisplay==0) {
cat(".")
if(saemix.options$displayProgress)
try(convplot.infit(allpar,saemix.options$nbiter.saemix[1],niter=(kiter-2)))
}
# Burn-in - resetting sufficient statistics
if(opt$flag.fmin && kiter==saemix.options$nbiter.sa) {
Uargs$COV1<-Uargs$COV[,Uargs$ind.fix11]
ind.prov<-!(varList$ind.eta %in% Uargs$i0.omega2)
varList$domega2<-varList$domega2[ind.prov,ind.prov,drop=FALSE] # keep in domega2 only indices of parameters with IIV
varList$ind0.eta<-Uargs$i0.omega2
varList$ind.eta<-1:(Uargs$nb.parameters)
if(length(varList$ind0.eta)>0) varList$ind.eta<-varList$ind.eta[!(varList$ind.eta %in% varList$ind0.eta)] # update ind.eta, now only parameters with IIV
Uargs$nb.etas<-length(varList$ind.eta)
suffStat$statphi1<-0
suffStat$statphi2<-0
suffStat$statphi3<-0
}
# E-step
xmcmc<-estep(kiter, Uargs, Dargs, opt, structural.model, mean.phi, varList, DYF, phiM)
varList<-xmcmc$varList
DYF<-xmcmc$DYF
phiM<-xmcmc$phiM
# psiM<-transphi(phiM,saemix.model["transform.par"])
# M-step
if(opt$stepsize[kiter]>0) {
############# Stochastic Approximation
xstoch<-mstep(kiter, Uargs, Dargs, opt, structural.model, DYF, phiM, varList, phi, betas, suffStat)
varList<-xstoch$varList
mean.phi<-xstoch$mean.phi
phi<-xstoch$phi
betas<-xstoch$betas
suffStat<-xstoch$suffStat
beta.I<-betas[Uargs$indx.betaI]
fixed.psi<-transphi(matrix(beta.I,nrow=1),saemix.model["transform.par"])
betaC<-betas[Uargs$indx.betaC]
var.eta<-mydiag(varList$omega)
l1<-betas.ini
l1[Uargs$indx.betaI]<-fixed.psi
l1[Uargs$indx.betaC]<-betaC
allpar[(kiter+1),]<-c(l1,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
} else { #end of loop on if (stepsize[kiter]>0)
allpar[(kiter+1),]<-allpar[kiter,]
}
theta<-c(fixed.psi,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
parpop[(kiter+1),]<-theta
# End of loop on kiter
}
etaM<-xmcmc$etaM # only need etaM here (re-created in estep otherwise)
cat("\n Minimisation finished\n")
print(date())
############# After end of iterations
fixed.effects<-0*betas
fixed.effects[Uargs$indx.betaI]<-fixed.psi
fixed.effects[Uargs$indx.betaC]<-betaC
varList$omega[Uargs$i0.omega2,]<-0
varList$omega[,Uargs$i0.omega2]<-0
##### Compute the individual parameters (MAP)
phi[,Uargs$i0.omega2,1:saemix.options$nb.chains]<-mean.phi[,Uargs$i0.omega2]
phi.samp<-phi
phi<-apply(phi,c(1,2),mean)
##### Conditional means and variances used for the estimation of the log-likelihood via Importance Sampling
cond.mean.phi<-phi
sphi1<-phi
sphi1[,varList$ind.eta]<-suffStat$statphi1
cond.mean.phi[,Uargs$i1.omega2]<-sphi1[,Uargs$i1.omega2]
cond.var.phi<-array(data=0,dim=dim(phi))
cond.var.phi[,Uargs$i1.omega2]<-suffStat$statphi3[,Uargs$i1.omega2]-cond.mean.phi[,Uargs$i1.omega2]**2
cond.mean.psi<-transphi(cond.mean.phi,saemixObject["model"]["transform.par"])
cond.mean.eta<-matrix(0,nrow=dim(etaM)[1],ncol=Uargs$nb.parameters)
cond.mean.eta[,varList$ind.eta]<-etaM
cond.mean.eta<-array(t(cond.mean.eta),dim=c(Uargs$nb.parameters, Dargs$N, saemix.options$nb.chains))
cond.mean.eta<-t(apply(cond.mean.eta,c(1,2),mean))
# Updating objects
saemix.model["Mcovariates"]<-Uargs$Mcovariates
saemix.model["indx.res"]<-Uargs$ind.res
saemix.model["indx.fix"]<-Uargs$indx.betaI
saemix.model["indx.cov"]<-Uargs$indx.betaC
saemix.model["indx.omega"]<-Uargs$i1.omega2
# Filling in result object
saemix.res<-new(Class="SaemixRes",name.fixed=saemix.model["name.fixed"], name.random=saemix.model["name.random"],name.sigma=saemix.model["name.sigma"], fixed.effects=c(fixed.effects),fixed.psi=c(fixed.psi),betas=betas,betaC=betaC, omega=varList$omega,respar=varList$pres,cond.mean.phi=cond.mean.phi,cond.var.phi=cond.var.phi, mean.phi=mean.phi, phi=phi,phi.samp=phi.samp,parpop=parpop,allpar=allpar,MCOV=varList$MCOV)
saemix.res["indx.res"]<-Uargs$ind.res
saemix.res["indx.fix"]<-Uargs$indx.betaI
saemix.res["indx.cov"]<-Uargs$indx.betaC
saemix.res["indx.omega"]<-Uargs$i1.omega2
saemix.res["npar.est"]<-Uargs$nb.parest
saemix.res["cond.mean.psi"]<-cond.mean.psi
saemix.res["cond.mean.eta"]<-cond.mean.eta
# Updating elements of saemixObject
saemixObject["model"]<-saemix.model
saemixObject["results"]<-saemix.res
saemixObject["options"]<-saemix.options
# saemixObject["rep.data"]<-chdat # Utile ? maybe remove rep.data
# ECO TODO check
# a la fin: mais verifier, pe pb de distribution ??? ie allpar sur l'echelle des betas et pas parpop ? a verifier
# saemix.res["allpar"]<-allpar
# saemix.res["parpop"]<-allpar[,-c(indx.betaC)]
#### Final computations
# Compute the MAP estimates of the PSI_i's
if(saemix.options$map) saemixObject<-map.saemix(saemixObject)
# Compute the Fisher Information Matrix & update saemix.res
if(saemix.options$fim) saemixObject<-fim.saemix(saemixObject)
# Estimate the log-likelihood via importance Sampling/Gaussian quadrature
if(saemix.options$ll.is) saemixObject<-llis.saemix(saemixObject)
if(saemix.options$ll.gq) saemixObject<-llgq.saemix(saemixObject)
#### Pretty printing the results (TODO finish in particular cov2cor)
if(saemix.options$print) print(saemixObject,digits=2)
#### Save the results to a file
if(saemix.options$save | saemix.options$save.graphs) {
# create directory to save the results
if(saemix.options$directory!="") xsave<-dir.create(saemix.options$directory)
if(!xsave) {
# Check that we're not trying to create a directory with the same name as a file
if(!file_test("-d",saemix.options$directory)) {
cat("Unable to create directory",saemix.options$directory)
saemix.options$directory<-"newdir"
dir.create(saemix.options$directory)
xsave<-file_test("-d",saemix.options$directory)
if(!xsave) {
saemix.options$directory<-""
xsave<-TRUE
cat(", saving in current directory.\n")
} else cat(", saving results in newdir instead.\n")
} else {
xsave<-TRUE
cat("Overwriting files in directory",saemix.options$directory,"\n")
}
}
}
if(saemix.options$save) {
namres<-ifelse(saemix.options$directory=="","pop_parameters.txt", file.path(saemix.options$directory,"pop_parameters.txt"))
xtry<-try(sink(namres))
if(!is(xtry,"try-error")) {
print(saemixObject)
sink()
namres<-ifelse(saemix.options$directory=="","indiv_parameters.txt", file.path(saemix.options$directory,"indiv_parameters.txt"))
if(length(saemixObject["results"]["map.psi"])>0)
write.table(saemixObject["results"]["map.psi"],namres,quote=FALSE, row.names=FALSE)
} else {
cat("Unable to save results, check writing permissions and/or path to directory.\n")
}
}
# ECO TODO finish, adding all
if(saemix.options$save.graphs) {
saemixObject<-saemix.predict(saemixObject)
if(saemix.options$directory=="") namgr<-"diagnostic_graphs.ps" else
namgr<-file.path(saemix.options$directory,"diagnostic_graphs.ps")
xtry<-try(postscript(namgr,horizontal=TRUE))
if(!is(xtry,"try-error")) {
par(mfrow=c(1,1))
try(plot(saemixObject,plot.type="data"))
try(plot(saemixObject,plot.type="convergence"))
if(length(saemixObject["results"]["ll.is"])>0) {
par(mfrow=c(1,1))
try(plot(saemixObject, plot.type="likelihood"))
}
try(plot(saemixObject,plot.type="observations.vs.predictions"))
try(plot(saemixObject,plot.type="random.effects"))
try(plot(saemixObject,plot.type="correlations"))
# Note: can replace all this by:
# default.saemix.plots(saemixObject)
dev.off()
if(saemix.options$directory=="") namgr<-"individual_fits.ps" else
namgr<-file.path(saemix.options$directory,"individual_fits.ps")
postscript(namgr,horizontal=FALSE)
try(plot(saemixObject,plot.type="individual.fit"))
dev.off()
} else {
cat("Unable to save results, check writing permissions and/or path to directory.\n")
}
}
options(warn=opt.warn)
return(saemixObject)
}
saemixdevelopment/saemix documentation built on May 27, 2020, 1:56 p.m.
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Defines functions saemix
Documented in saemix
#' Stochastic Approximation Expectation Maximization (SAEM) algorithm
#'
#' SAEM algorithm perform parameter estimation for nonlinear mixed effects
#' models without any approximation of the model (linearization, quadrature
#' approximation, . . . )
#'
#' The SAEM algorithm is a stochastic approximation version of the standard EM
#' algorithm proposed by Kuhn and Lavielle (see reference). Details of the
#' algorithm can be found in the pdf file accompanying the package.
#'
#' @name saemix
#' @aliases initialiseMainAlgo mstep estep
#'
#' @param model an object of class SaemixModel, created by a call to the
#' function \code{\link{saemixModel}}
#' @param data an object of class SaemixData, created by a call to the function
#' \code{\link{saemixData}}
#' @param control a list of options, see \code{\link{saemixControl}}
#' @return An object of class SaemixObject containing the results of the fit of
#' the data by the non-linear mixed effect model. A summary of the results is
#' printed out to the terminal, and, provided the appropriate options have not
#' been changed, numerical and graphical outputs are saved in a directory.
#' @author Emmanuelle Comets <emmanuelle.comets@@inserm.fr>, Audrey Lavenu,
#' Marc Lavielle.
#' @seealso \code{\link{SaemixData}},\code{\link{SaemixModel}},
#' \code{\link{SaemixObject}}, \code{\link{saemixControl}},
#' \code{\link{plot.saemix}}
#' @references Comets E, Lavenu A, Lavielle M. Parameter estimation in nonlinear mixed effect models using saemix, an R implementation of the SAEM algorithm. Journal of Statistical Software 80, 3 (2017), 1-41.
#'
#' Kuhn E, Lavielle M. Maximum likelihood estimation in nonlinear mixed effects models. Computational Statistics and Data Analysis 49, 4 (2005), 1020-1038.
#'
#' Comets E, Lavenu A, Lavielle M. SAEMIX, an R version of the SAEM algorithm.
#' 20th meeting of the Population Approach Group in Europe, Athens, Greece
#' (2011), Abstr 2173.
#' @keywords models
#' @examples
#'
#' data(theo.saemix)
#'
#' saemix.data<-saemixData(name.data=theo.saemix,header=TRUE,sep=" ",na=NA,
#' name.group=c("Id"),name.predictors=c("Dose","Time"),
#' name.response=c("Concentration"),name.covariates=c("Weight","Sex"),
#' units=list(x="hr",y="mg/L", covariates=c("kg","-")), name.X="Time")
#'
#' model1cpt<-function(psi,id,xidep) {
#' dose<-xidep[,1]
#' tim<-xidep[,2]
#' ka<-psi[id,1]
#' V<-psi[id,2]
#' CL<-psi[id,3]
#' k<-CL/V
#' ypred<-dose*ka/(V*(ka-k))*(exp(-k*tim)-exp(-ka*tim))
#' return(ypred)
#' }
#'
#' saemix.model<-saemixModel(model=model1cpt,
#' description="One-compartment model with first-order absorption",
#' psi0=matrix(c(1.,20,0.5,0.1,0,-0.01),ncol=3, byrow=TRUE,
#' dimnames=list(NULL, c("ka","V","CL"))),transform.par=c(1,1,1),
#' covariate.model=matrix(c(0,1,0,0,0,0),ncol=3,byrow=TRUE),fixed.estim=c(1,1,1),
#' covariance.model=matrix(c(1,0,0,0,1,0,0,0,1),ncol=3,byrow=TRUE),
#' omega.init=matrix(c(1,0,0,0,1,0,0,0,1),ncol=3,byrow=TRUE),error.model="constant")
#'
#'
#' # Not run (strict time constraints for CRAN)
#' # saemix.fit<-saemix(saemix.model,saemix.data,list(seed=632545,directory="newtheo",
#' # save=FALSE,save.graphs=FALSE))
#'
#' # Prints a summary of the results
#' # print(saemix.fit)
#'
#' # Outputs the estimates of individual parameters
#' # psi(saemix.fit)
#'
#' # Shows some diagnostic plots to evaluate the fit
#' # plot(saemix.fit)
#'
#'
#' @export saemix
saemix<-function(model,data,control=list()) {
# Convergence plots during fit (special function, not user-level)
convplot.infit<-function(allpar,K1,niter=0) {
# Convergence plots for all the fixed effects, random effects and residual variability
np<-dim(allpar)[2]
K<-dim(allpar)[1]
n1<-round(sqrt(np))
n2<-ceiling(np/n1)
if(n1>5 | n2>5) {n1<-3;n2<-4}
if(niter==0) niter<-K
par(mfrow=c(n1,n2))
for(j in 1:np) {
plot(1:niter,allpar[1:niter,j],type="l", xlab="Iteration", ylab=colnames(allpar)[j])
abline(v=K1)
}
}
if(!is(model,"SaemixModel")) {
cat("Please provide a valid model object (see the help page for SaemixModel)\n")
return()
}
if(!is(data,"SaemixData")) {
cat("Please provide a valid data object (see the help page for SaemixData)\n")
return()
}
saemixObject<-new(Class="SaemixObject",data=data,model=model,options=control)
# saemixObject<-new(Class="SaemixObject",data=saemix.data, model=saemix.model,options=saemix.options)
opt.warn<-getOption("warn")
if(!saemixObject["options"]$warnings) options(warn=-1)
saemix.options<-saemixObject["options"]
saemix.model<-saemixObject["model"]
saemix.data<-saemixObject["data"]
saemix.data@ocov<-saemix.data@ocov[saemix.data@data[,"mdv"]==0,,drop=FALSE]
saemix.data@data<-saemix.data@data[saemix.data@data[,"mdv"]==0,]
saemix.data@ntot.obs<-dim(saemix.data@data)[1]
# showall(saemixObject)
# Initialising random generator
OLDRAND<-TRUE
set.seed(saemix.options$seed)
############################################
# Main Algorithm
############################################
# Initialisation - creating several lists with necessary information extracted (Uargs, Dargs, opt,varList, suffStat)
xinit<-initialiseMainAlgo(saemix.data,saemix.model,saemix.options)
saemix.model<-xinit$saemix.model
Dargs<-xinit$Dargs
Uargs<-xinit$Uargs
varList<-xinit$varList
phiM<-xinit$phiM
mean.phi<-xinit$mean.phi
DYF<-xinit$DYF
opt<-xinit$opt
betas<-betas.ini<-xinit$betas
fixed.psi<-xinit$fixedpsi.ini
var.eta<-varList$diag.omega
theta0<-c(fixed.psi,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
parpop<-matrix(data=0,nrow=(saemix.options$nbiter.tot+1),ncol=(Uargs$nb.parameters+length(Uargs$i1.omega2)+length(saemix.model["indx.res"])))
colnames(parpop)<-c(saemix.model["name.modpar"], saemix.model["name.random"], saemix.model["name.sigma"][saemix.model["indx.res"]])
allpar<-matrix(data=0,nrow=(saemix.options$nbiter.tot+1), ncol=(Uargs$nb.betas+length(Uargs$i1.omega2)+length(saemix.model["indx.res"])))
colnames(allpar)<-c(saemix.model["name.fixed"],saemix.model["name.random"], saemix.model["name.sigma"][saemix.model["indx.res"]])
parpop[1,]<-theta0
allpar[1,]<-xinit$allpar0
# using several Markov chains - only useful if passed back to main routine...
# chdat<-new(Class="SaemixRepData",data=saemix.data, nb.chains=saemix.options$nb.chains)
# NM<-chdat["NM"]
# IdM<-chdat["dataM"]$IdM
# yM<-chdat["dataM"]$yM
# XM<-chdat["dataM"][,saemix.data["name.predictors"],drop=FALSE]
# List of sufficient statistics - change during call to stochasticApprox
suffStat<-list(statphi1=0,statphi2=0,statphi3=0,statrese=0)
phi<-array(data=0,dim=c(Dargs$N, Uargs$nb.parameters, saemix.options$nb.chains))
# structural model, check nb of parameters
structural.model<-saemix.model["model"]
# nb.parameters<-saemix.model["nb.parameters"]
# Running the algorithm
# hw=waitbar(1,'Estimating the population parameters (SAEM). Wait...');
if(saemix.options$displayProgress) par(ask=FALSE)
cat("Running main SAEM algorithm\n")
print(date())
for (kiter in 1:saemix.options$nbiter.tot) { # Iterative portion of algorithm
# SAEM convergence plots
if(kiter%%saemix.options$nbdisplay==0) {
cat(".")
if(saemix.options$displayProgress)
try(convplot.infit(allpar,saemix.options$nbiter.saemix[1],niter=(kiter-2)))
}
# Burn-in - resetting sufficient statistics
if(opt$flag.fmin && kiter==saemix.options$nbiter.sa) {
Uargs$COV1<-Uargs$COV[,Uargs$ind.fix11]
ind.prov<-!(varList$ind.eta %in% Uargs$i0.omega2)
varList$domega2<-varList$domega2[ind.prov,ind.prov,drop=FALSE] # keep in domega2 only indices of parameters with IIV
varList$ind0.eta<-Uargs$i0.omega2
varList$ind.eta<-1:(Uargs$nb.parameters)
if(length(varList$ind0.eta)>0) varList$ind.eta<-varList$ind.eta[!(varList$ind.eta %in% varList$ind0.eta)] # update ind.eta, now only parameters with IIV
Uargs$nb.etas<-length(varList$ind.eta)
suffStat$statphi1<-0
suffStat$statphi2<-0
suffStat$statphi3<-0
}
# E-step
xmcmc<-estep(kiter, Uargs, Dargs, opt, structural.model, mean.phi, varList, DYF, phiM)
varList<-xmcmc$varList
DYF<-xmcmc$DYF
phiM<-xmcmc$phiM
# psiM<-transphi(phiM,saemix.model["transform.par"])
# M-step
if(opt$stepsize[kiter]>0) {
############# Stochastic Approximation
xstoch<-mstep(kiter, Uargs, Dargs, opt, structural.model, DYF, phiM, varList, phi, betas, suffStat)
varList<-xstoch$varList
mean.phi<-xstoch$mean.phi
phi<-xstoch$phi
betas<-xstoch$betas
suffStat<-xstoch$suffStat
beta.I<-betas[Uargs$indx.betaI]
fixed.psi<-transphi(matrix(beta.I,nrow=1),saemix.model["transform.par"])
betaC<-betas[Uargs$indx.betaC]
var.eta<-mydiag(varList$omega)
l1<-betas.ini
l1[Uargs$indx.betaI]<-fixed.psi
l1[Uargs$indx.betaC]<-betaC
allpar[(kiter+1),]<-c(l1,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
} else { #end of loop on if (stepsize[kiter]>0)
allpar[(kiter+1),]<-allpar[kiter,]
}
theta<-c(fixed.psi,var.eta[Uargs$i1.omega2],varList$pres[Uargs$ind.res])
parpop[(kiter+1),]<-theta
# End of loop on kiter
}
etaM<-xmcmc$etaM # only need etaM here (re-created in estep otherwise)
cat("\n Minimisation finished\n")
print(date())
############# After end of iterations
fixed.effects<-0*betas
fixed.effects[Uargs$indx.betaI]<-fixed.psi
fixed.effects[Uargs$indx.betaC]<-betaC
varList$omega[Uargs$i0.omega2,]<-0
varList$omega[,Uargs$i0.omega2]<-0
##### Compute the individual parameters (MAP)
phi[,Uargs$i0.omega2,1:saemix.options$nb.chains]<-mean.phi[,Uargs$i0.omega2]
phi.samp<-phi
phi<-apply(phi,c(1,2),mean)
##### Conditional means and variances used for the estimation of the log-likelihood via Importance Sampling
cond.mean.phi<-phi
sphi1<-phi
sphi1[,varList$ind.eta]<-suffStat$statphi1
cond.mean.phi[,Uargs$i1.omega2]<-sphi1[,Uargs$i1.omega2]
cond.var.phi<-array(data=0,dim=dim(phi))
cond.var.phi[,Uargs$i1.omega2]<-suffStat$statphi3[,Uargs$i1.omega2]-cond.mean.phi[,Uargs$i1.omega2]**2
cond.mean.psi<-transphi(cond.mean.phi,saemixObject["model"]["transform.par"])
cond.mean.eta<-matrix(0,nrow=dim(etaM)[1],ncol=Uargs$nb.parameters)
cond.mean.eta[,varList$ind.eta]<-etaM
cond.mean.eta<-array(t(cond.mean.eta),dim=c(Uargs$nb.parameters, Dargs$N, saemix.options$nb.chains))
cond.mean.eta<-t(apply(cond.mean.eta,c(1,2),mean))
# Updating objects
saemix.model["Mcovariates"]<-Uargs$Mcovariates
saemix.model["indx.res"]<-Uargs$ind.res
saemix.model["indx.fix"]<-Uargs$indx.betaI
saemix.model["indx.cov"]<-Uargs$indx.betaC
saemix.model["indx.omega"]<-Uargs$i1.omega2
# Filling in result object
saemix.res<-new(Class="SaemixRes",name.fixed=saemix.model["name.fixed"], name.random=saemix.model["name.random"],name.sigma=saemix.model["name.sigma"], fixed.effects=c(fixed.effects),fixed.psi=c(fixed.psi),betas=betas,betaC=betaC, omega=varList$omega,respar=varList$pres,cond.mean.phi=cond.mean.phi,cond.var.phi=cond.var.phi, mean.phi=mean.phi, phi=phi,phi.samp=phi.samp,parpop=parpop,allpar=allpar,MCOV=varList$MCOV)
saemix.res["indx.res"]<-Uargs$ind.res
saemix.res["indx.fix"]<-Uargs$indx.betaI
saemix.res["indx.cov"]<-Uargs$indx.betaC
saemix.res["indx.omega"]<-Uargs$i1.omega2
saemix.res["npar.est"]<-Uargs$nb.parest
saemix.res["cond.mean.psi"]<-cond.mean.psi
saemix.res["cond.mean.eta"]<-cond.mean.eta
# Updating elements of saemixObject
saemixObject["model"]<-saemix.model
saemixObject["results"]<-saemix.res
saemixObject["options"]<-saemix.options
# saemixObject["rep.data"]<-chdat # Utile ? maybe remove rep.data
# ECO TODO check
# a la fin: mais verifier, pe pb de distribution ??? ie allpar sur l'echelle des betas et pas parpop ? a verifier
# saemix.res["allpar"]<-allpar
# saemix.res["parpop"]<-allpar[,-c(indx.betaC)]
#### Final computations
# Compute the MAP estimates of the PSI_i's
if(saemix.options$map) saemixObject<-map.saemix(saemixObject)
# Compute the Fisher Information Matrix & update saemix.res
if(saemix.options$fim) saemixObject<-fim.saemix(saemixObject)
# Estimate the log-likelihood via importance Sampling/Gaussian quadrature
if(saemix.options$ll.is) saemixObject<-llis.saemix(saemixObject)
if(saemix.options$ll.gq) saemixObject<-llgq.saemix(saemixObject)
#### Pretty printing the results (TODO finish in particular cov2cor)
if(saemix.options$print) print(saemixObject,digits=2)
#### Save the results to a file
if(saemix.options$save | saemix.options$save.graphs) {
# create directory to save the results
if(saemix.options$directory!="") xsave<-dir.create(saemix.options$directory)
if(!xsave) {
# Check that we're not trying to create a directory with the same name as a file
if(!file_test("-d",saemix.options$directory)) {
cat("Unable to create directory",saemix.options$directory)
saemix.options$directory<-"newdir"
dir.create(saemix.options$directory)
xsave<-file_test("-d",saemix.options$directory)
if(!xsave) {
saemix.options$directory<-""
xsave<-TRUE
cat(", saving in current directory.\n")
} else cat(", saving results in newdir instead.\n")
} else {
xsave<-TRUE
cat("Overwriting files in directory",saemix.options$directory,"\n")
}
}
}
if(saemix.options$save) {
namres<-ifelse(saemix.options$directory=="","pop_parameters.txt", file.path(saemix.options$directory,"pop_parameters.txt"))
xtry<-try(sink(namres))
if(!is(xtry,"try-error")) {
print(saemixObject)
sink()
namres<-ifelse(saemix.options$directory=="","indiv_parameters.txt", file.path(saemix.options$directory,"indiv_parameters.txt"))
if(length(saemixObject["results"]["map.psi"])>0)
write.table(saemixObject["results"]["map.psi"],namres,quote=FALSE, row.names=FALSE)
} else {
cat("Unable to save results, check writing permissions and/or path to directory.\n")
}
}
# ECO TODO finish, adding all
if(saemix.options$save.graphs) {
saemixObject<-saemix.predict(saemixObject)
if(saemix.options$directory=="") namgr<-"diagnostic_graphs.ps" else
namgr<-file.path(saemix.options$directory,"diagnostic_graphs.ps")
xtry<-try(postscript(namgr,horizontal=TRUE))
if(!is(xtry,"try-error")) {
par(mfrow=c(1,1))
try(plot(saemixObject,plot.type="data"))
try(plot(saemixObject,plot.type="convergence"))
if(length(saemixObject["results"]["ll.is"])>0) {
par(mfrow=c(1,1))
try(plot(saemixObject, plot.type="likelihood"))
}
try(plot(saemixObject,plot.type="observations.vs.predictions"))
try(plot(saemixObject,plot.type="random.effects"))
try(plot(saemixObject,plot.type="correlations"))
# Note: can replace all this by:
# default.saemix.plots(saemixObject)
dev.off()
if(saemix.options$directory=="") namgr<-"individual_fits.ps" else
namgr<-file.path(saemix.options$directory,"individual_fits.ps")
postscript(namgr,horizontal=FALSE)
try(plot(saemixObject,plot.type="individual.fit"))
dev.off()
} else {
cat("Unable to save results, check writing permissions and/or path to directory.\n")
}
}
options(warn=opt.warn)
return(saemixObject)
}
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