Hello, I'm trying to run an lmer model with family poisson but receive the following warning message:
model<-lmer(count~tem+dat+alt+year+tem:dat+tem:alt+tem:year+dat:alt+dat:year+alt:year+(1|id),family=poisson) Error in objective(.par, ...) : Leading minor of order 2 in downdated X'X is not positive definite I'm using the newest version of R and recently installed the following libraries: (lme4, matrix, lattice). I don't understand what the warning message means or know how to fix it, please help! My response variable is a count variable (n=551); 212 with value = 0, and the rest range between 1-3. -- View this message in context: http://www.nabble.com/warning-message-for-lmer-model-with-poisson-family-tp17659512p17659512.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.