Hello -- I posted this question yesterday and for some reason the post seems to be attached to the wrong thread. Also, I extended my test a little and it seems to indicate the problem is with spm. I would appreciate any help. Thanks.
========================================================== library(plyr) library(SemiPar) data <- data.frame(id=c(rep("111",100),rep("222",200)), value=c(rnorm(100,2,1),rnorm(200,10,5)), lhs=c(rnorm(100,2,1),rnorm(200,10,5))) #this works d_ply(data, c("id"), function(x) { print(lm("lhs~value", data=x)) }) #this works data111 <- data[data$id=="111",] print(spm(data111$value ~ f(1:nrow(data111)))) #this does not work d_ply(data, c("id"), function(x) { print(spmx <- spm(x$value ~ f(1:nrow(x)))) }) ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.