Hi there, I'm trying to do multivariate ANOVA and have a bit trouble with the following code: <hansl> nulldata 8 matrix Y={9,4;10,2;11,0;2,3;4,4;6,5;1,5;5,9} matrix G={1;1;1;2;2;2;3;3} matrix T=mcov(Y)*(rows(Y)-1) eval T matrix Ns =zeros(rows(uniq(G)),1) #*How to get to the Sum of squared residuals?* matrix Y_g1=Y[1:3,] matrix Y_g2=Y[4:6,] matrix Y_g3=Y[7:8,] matrix C={} matrix C1=mcov(Y_g1)*(rows(Y_g1)-1) matrix C2=mcov(Y_g2)*(rows(Y_g2)-1) matrix C3=mcov(Y_g3)*(rows(Y_g3)-1) matrix C=C1+C2+C3 eval C matrix C={} loop for g=1..rows(Ns) #C+=mcov(Y_g$g)*(rows(Y_g$g)-1) * C+=C$g* *# this is not working* endloop eval C <hansl> Up until now I did not find a way to get to know the number of obs per group or the indices for the the matrices matrix Y_g*. Should work with some loop construction. However, what do you thing of giving the function cdemean a second argument that demeans the columns according to the structure of the groups as in G: *C=cdemean(Y,G)'cdemean(Y,G)' * Cheers Leon Unger* *