Re: [R] Error message in lmer
I do not think anyone has answered this. I'm trying to run a simple one-way ANCOVA with the lmer function in R package lme4, but have encountered some conceptual problem. The data file MyData.txt is like this: Group Subj Cov Resp A1 3.90 4.05 A 2 4.05 4.25 A 3 4.25 3.60 A 4 3.60 4.20 A 5 4.20 4.05 A 6 4.05 3.85 B 7 3.85 4.15 B 8 4.15 4.60 B 9 4.60 4.15 B 10 4.15 4.40 B 11 4.40 3.35 B 12 3.35 3.80 B 13 3.80 3.90 Since I would like to treat subject (Subj) as a random factor, my one- way ANCOVA (with covariate, Cov) is: This is a conceptual problem, indeed. To be able to estimate a subject effect, you need to have repeated measurements (several lines) per observed subject ... Cheers, Lorenz __ R-help@stat.math.ethz.ch 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.
Re: [R] Error message in lmer
Thanks a lot for the response and explanation, Lorenz! It seems that I can run the analysis with 'lm' without treating subject as a random factor lm(Resp ~ Group*Cov, TestData) Thanks, Gang On Aug 2, 2007, at 5:09 AM, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: I do not think anyone has answered this. I'm trying to run a simple one-way ANCOVA with the lmer function in R package lme4, but have encountered some conceptual problem. The data file MyData.txt is like this: Group Subj Cov Resp A1 3.90 4.05 A 2 4.05 4.25 A 3 4.25 3.60 A 4 3.60 4.20 A 5 4.20 4.05 A 6 4.05 3.85 B 7 3.85 4.15 B 8 4.15 4.60 B 9 4.60 4.15 B 10 4.15 4.40 B 11 4.40 3.35 B 12 3.35 3.80 B 13 3.80 3.90 Since I would like to treat subject (Subj) as a random factor, my one- way ANCOVA (with covariate, Cov) is: TestData=read.table(MyData.txt, header=T); m1 - lmer(Resp ~ Group * Cov + (1 | Subj), TestData) This is a conceptual problem, indeed. To be able to estimate a subject effect, you need to have repeated measurements (several lines) per observed subject ... Cheers, Lorenz __ R-help@stat.math.ethz.ch 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.
[R] Error message in lmer
I'm trying to run a simple one-way ANCOVA with the lmer function in R package lme4, but have encountered some conceptual problem. The data file MyData.txt is like this: Group Subj Cov Resp A 1 3.90 4.05 A2 4.05 4.25 A3 4.25 3.60 A4 3.60 4.20 A5 4.20 4.05 A6 4.05 3.85 B7 3.85 4.15 B8 4.15 4.60 B9 4.60 4.15 B10 4.15 4.40 B11 4.40 3.35 B12 3.35 3.80 B13 3.80 3.90 Since I would like to treat subject (Subj) as a random factor, my one- way ANCOVA (with covariate, Cov) is: TestData=read.table(MyData.txt, header=T); m1 - lmer(Resp ~ Group * Cov + (1 | Subj), TestData) but I got the following error message: Error in lmerFactorList(formula, mf, fltype) : number of levels in grouping factor(s) 'Subj' is too large Do I have some misconception about the model? Thank you very much. Gang __ R-help@stat.math.ethz.ch 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.
