Hi, I have a dataset that is stratified by 3 levels, with an unequal number of observations per strata: A B C 182 182 91 The data are approximately normally distrubuted. Is there any reason why I can NOT use TukeyHSD to do pair-wise comparison of means? Any thoughts or references would be greatly appreciated. Thanks, Dylan -- Dylan Beaudette Soil Resource Laboratory http://casoilresource.lawr.ucdavis.edu/ University of California at Davis 530.754.7341