search for: newtheta

...lt;-w wmis[floor(runif(10,1,n))]<-NA dat<-as.data.frame(cbind(wmis,ymis,x1,x2,x3,x4)) s <- prelim.mix(dat,3) # do preliminary manipulations thetahat <- em.mix(s) # ML estimate for unrestricted model rngseed(1234567) # set random number generator seed newtheta <- da.mix(s,thetahat,steps=100) # data augmentation ximp <- imp.mix(s, newtheta, dat) # impute under newtheta ################################################################ Your mix package is important part of our ongoing research on the missing data project and we would like to hav...

...ender1 x<-cbind(data$gender,data$ipip,data$ideol,data$prtyid, data$wage1992) colnames(x)<-c("gender","ipip", "ideol", "prtyid","wage") # start imputation s <- prelim.mix(x,4) thetahat <- em.mix(s) And here comes the error message: > newtheta <- da.mix(s,thetahat, steps=100,showits=TRUE) Steps of Data Augmentation: 1...Error in da.mix(s, thetahat, steps = 100, showits = TRUE) : Improper posterior--empty cells > imp.mix(s, newtheta, x)

...#<-- set random number generator seed margins<-c(1,2) #<-- I have two categorical variables, if I had three, the margin=c(1,2,3) design<-matrix(c(1,1,1,1,0,1,0,1,0,0,1,1),ncol=3) for (i in 1:5){ cat("Doing imputation ",i,"\n") thetahat <- ecm.mix(s,margins,design) newtheta <- dabipf.mix(s, margins,design,thetahat, steps=2000, showits=TRUE) MI[[i]] <- imp.mix(s, newtheta) } Steps of ECM: 1...2...3...4...5...6...7...8...9...10...11...12...13...14...15...16...17... 18...19...20...21...22...23...24...25...26... Steps of Data Augmentation-Bayesian IPF: 1...2...Er...

...matique > # Parameter estimation > system.time(thetahat<-em.mix(s,showits=TRUE)) Erreur dans rep(prior, s$ncells) : argument 'times' incorrect Timing stopped at: 0 0 0 ### indeed : s$ncells is NA ! ### Therefore, the rest crashes : > # Data augmentation proper > system.time(newtheta <- da.mix(s, thetahat, steps=100, showits=TRUE)) Erreur dans rep(prior, s$ncells) : argument 'times' incorrect Timing stopped at: 0 0 0 > # Single imputation... > system.time(ximp1 <- imp.mix(s, newtheta)) Erreur dans imp.mix(s, newtheta) : objet 'newtheta' introuvable...

...-------------------# MI<-vector("list",10) #<--vector of complete data after MI fit.model.mi<-vector("list",10) rngseed(1234567) #<-- set random number generator seed for (i in 1:10){ cat("Doing imputation ",i,"\n") thetahat <- em.mix(s) newtheta <- da.mix(s, thetahat, steps=2000, showits=TRUE) MI[[i]] <- imp.mix(s, newtheta) } Here is help file about mix Help files with alias or concept or title matching 'mix' using regular expression matching: glmmPQL(MASS) Fit Generalized Linear Mixed Models via PQL gamm(...