Hi all, I am doing analysis of variance. Suppose y is an observed probe intensity value then a main effects model is y = Array + probe + error Suppose there is information about the locations of probes relative to 3' end and suppose the distances from 3' fall in 2 categories (X,Y). I am searching for a code that will enable me to partiotion probe-effect on the basis of the distance categories (X,Y). I want to have ANOVA table of the form, say Sources of variation DF SS MSS F Array 20 A Probe 30 B X 10 C Y 20 D where C+D = B. Thanks for your help. Stephen.