linear mixed model using lmer
Do you really think a variance from a sample size of 2 makes any sense? Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Fri, Mar 4, 2022 at 5:06 PM array chip via R-help
<r-help at r-project.org> wrote:
Thanks Jeff for reminding me that the attachment is removed. I put it in my google drive if anyone wants to test the data (https://drive.google.com/file/d/1lgVZVLHeecp9a_sFxEPeg6353O-qXZhM/view?usp=sharing) I'll try the mixed model mailing list as well. John On Friday, March 4, 2022, 04:56:20 PM PST, Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote: a) There is a mailing list for that: https://stat.ethz.ch/mailman/listinfo/r-sig-mixed-models b) Read the Posting Guide, as most attachment types are removed to avoid propagating worms/viruses. (None seen upon receipt of this email.) On March 4, 2022 4:41:57 PM PST, array chip via R-help <r-help at r-project.org> wrote:
Dear all, I have this simple dataset to measure the yeild of a crop collected in 2 batches (attached). when I ran a simple inear mixed model using lmer to estimate within-batch and between-batch variability, the between-batch variability is 0. The run showed that data is singular. Does anyone know why the data is singular and what's the reason for 0 variability? is it because the dataset only has 2 batches?
daty<-read.table("datx.txt",sep='\t',header=T,row.names=NULL)
library(lme4)> lmer(yield~1+(1|batch),daty)
boundary (singular) fit: see ?isSingular
Linear mixed model fit by REML ['lmerMod']
Formula: yield ~ 1 + (1 | batch)
Data: daty
REML criterion at convergence: 115.6358
Random effects:
Groups Name Std.Dev.
batch (Intercept) 0.000
Residual 2.789
Number of obs: 24, groups: batch, 2
Fixed Effects:
(Intercept)
5.788
Thanks!
John
--
Sent from my phone. Please excuse my brevity.
[[alternative HTML version deleted]]
______________________________________________ R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.