R/em.R

In tonizhong/SMARTAR: Sequential Multiple Assignment Randomized Trial and Adaptive Randomization

#em() combine two method of estimation for DTR value
#"Gest" for method option indicates
#"G-estimation method"; "IPW" indicates
#"Inversed Probability Weighting method"

em<-function(data,method="Gest"){
   D<-as.data.frame(data)
   if (is.null(D$O1)) {Base<-0} else {Base<-1}
   Nstage<-nstage(data=D)
   Dmat<-atsscan(data=D)
   G<-nrow(Dmat)
   #total number of strategies defined in input dataset
   umat<-NULL

   if (Nstage==1 && Base==0) {
     for (g in seq(G)){
     if (method=="Gest") {eu<-gemean(data=D,ats=Dmat[g,2])} else
     if (method=="IPW") {eu<-memean(data=D,ats=Dmat[g,2])} else
       stop("invalid enter for argument 'method'")
     umat<-rbind(umat,c(Dmat[g,],eu))
     colnames(umat)<-c("ATS","d0","N","value")}} else
   if (Nstage==1 && Base==1) {
     for (g in seq(G)){
      if (method=="Gest") {eu<-gemean(data=D,ats=Dmat[g,2:3])} else
      if (method=="IPW")  {eu<-memean(data=D,ats=Dmat[g,2:3])} else
        stop("invalid enter for argument 'method'")
      umat<-rbind(umat,c(Dmat[g,],eu))
      colnames(umat)<-c("ATS","d0","d1","N","value")}} else
   if (Nstage==2 && Base==0) {
     for (g in seq(G)){
     if (method=="Gest") {eu<-gemean(data=D,ats=Dmat[g,2:4])}
       else
     if (method=="IPW")  {eu<-memean(data=D,ats=Dmat[g,2:4])} else
       stop("invalid enter for argument 'method'")
     umat<-rbind(umat,c(Dmat[g,],eu))
     colnames(umat)<-c("ATS","d0","d00","d01","N","value")}}
   else
   if (Nstage==2 && Base==1) {
     for (g in seq(G)){
     if (method=="Gest") {eu<-gemean(data=D,ats=Dmat[g,2:7])}
       else
     if (method=="IPW")  {eu<-memean(data=D,ats=Dmat[g,2:7])} else
       stop("invalid enter for argument 'method'")
     umat<-rbind(umat,c(Dmat[g,],eu))
     colnames(umat)<-c("ATS","d0","d1","d00","d01","d10","d11","N","value")}}
   else
   if (Nstage==3 && Base==0) {
     for (g in seq(G)){
     if (method=="Gest") {eu<-gemean(data=D,ats=Dmat[g,2:8])}
       else
     if (method=="IPW")  {eu<-memean(data=D,ats=Dmat[g,2:8])} else
       stop("invalid enter for argument 'method'")
     umat<-rbind(umat,c(Dmat[g,],eu))
     colnames(umat)<-c("ATS","d0","d00","d01","d000",
                      "d001","d010","d011","N","value")}}
 
   umat<-as.data.frame(umat)
   return(umat)
}