Mixed Models – Part 1

February 3, 2011

(This article was first published on Matt's Stats n stuff » R, and kindly contributed to R-bloggers)

Very brief. Have been exploring mixed models in R using nlme::lme. Am looking forward to understanding them more, they’re going to be used more and more in years to come I’ve no doubt of that.

Here are some scripts, very rough, for diagnostics when running simple 2 levels, or models with 1 grouping variable.

CLICK HERE – To download the first section of diagnostics

CLICK HERE – To download the second section of diagnostics

To use simply run:
source("..my_directoy/mixed_model_diag_1_v1.0.R")
then:
mm.diag.1(my.model)
where ‘my.model’ is the output of an ‘lme’.

This code is derived largely from code prepared by Andrew Robinson whose guide icebreakeR is freely available and a highly recommended read for both R beginneRs or experienced R users looking to dabble in mixed models for the first time http://www.ms.unimelb.edu.au/~andrewpr/r-users/. I take 0 credit for this code.