Dear all, I am using "coxme" function in Kinship library to fit random treatment effect nested within centre. I got 3 treatments (0,1,2) and 3 centres. I used following commands, but got an error.
ugroup=paste(rep(1:3,each=3),rep(0:2,3),sep='/') mat1=bdsmatrix(rep(c(1,1,1,1,1,1,1,1,1),3),blocksize=rep(3,3),dimnames=list(ugroup,ugroup)) mat2=bdsmatrix(rep(c(0,0,0,0,0,0,0,0,1),3),blocksize=rep(3,3),dimnames=list(ugroup,ugroup)) group=paste(dat1$centre,dat1$treat,sep='/') coxme(Surv(time,status) ~ as.factor(treat), data=dat1,random= ~1|group,varlist=list(mat1,mat2),rescale=F,pdcheck=FALSE)
Error in coxme.fit(X, Y, strats, offset, init, control, weights = weights, :
Random effects variance is not spd
Could anyone help me correcting this error?
Many thanks in advance.
Ruwanthi
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