On Fri, Mar 6, 2009 at 6:07 AM, Sueli Rodrigues <srodr...@esalq.usp.br> wrote: > > Hi, I have the following file, and I need to work out the linear > regression for each sample. I tried the model(*) and receive the error > message (**): >> data=split(mydata,rep(1:(nrow(mydata)/6),each=6)) >> arrang.linear=lapply(data,lm,formula=KA~PA) > Erro em storage.mode(y) <- "double" : > invalid to change the storage mode of a factor > Além disso: Warning message: > In model.response(mf, "numeric") : > using type="numeric" with a factor response will be ignored > > SAMPLE PA KA > 2 0.917 11.261 > 2 0.823 11.010 > 2 0.803 10.381 > 2 0.744 10.208 > 2 0.697 10.006 > 2 0.681 9.916 > 3 0.789 10.271 > 3 0.702 10.076 > 3 0.692 9.990 > 3 0.646 9.779 > 3 0.620 9.749 > 3 0.608 9.708 > 4 1.052 11.779 > 4 0.941 11.249 > 4 0.881 10.140 > 4 0.824 10.052 > 4 0.790 9.859 > . . . > . . . > . . . > 80 0.499 9.819
The lmList function in the package nlme is designed to handle situations like this. Try library(nlme) modlst <- lmList(KA ~ PA | SAMPLE, data) ______________________________________________ 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.
