Hi everyone, How to constrain the residual variance to be 0 when using the lmer function? Wen Luo Wen Luo, Ph.D. Assistant Professor Department of Educational Psychology University of Wisconsin -- Milwaukee Enderis Hall 759 P.O. Box 413 Milwaukee, WI 53201-0413 Office: 414 229 4998 Fax: 414 229 4939 luo at uwm.edu