It seems that what I need to get the within group component is as.numeric(VarCorr(fm1Rail.lme)[2,2]) thanks to Bert Gunter and Peter Alspach. Murray Jorgensen -- Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html Department of Statistics, University of Waikato, Hamilton, New Zealand Email: maj at waikato.ac.nz Fax 7 838 4155 Phone +64 7 838 4773 wk Home +64 7 825 0441 Mobile 021 1395 862