Hello, I encountered some difficulities using loglm() from MASS package. I had to fit several (about 20) models to the same dataset and than compare the fitted values. Each time a call to loglm() looks like loglm(freq ~ x + y + y*z , data=d) where d is a data.frame containing a bunch of factors x, y, z ... as well as a vector of frequencies (freq). For each created model object somewhere later I used fitted() to obtain fitted values. The result returned was always an array. Unfortunately for different models its structure (i.e. dim attribute) is different (probably because of different ordering of the factors in the model formulas). That makes any calculations on those arrays very tedious. Actually I would expect fitted(loglm(freq ~ x)) to return a vector and fitted(loglm(~ x)) to return an array. Just to preserve the structure of entered observed frequencies. Correct me if I''m wrong. Is there a good remedy for the problem above apart from comparing array structures ,,by hand'''' and than using aperm() to make all of them comformable? I would be very gratefull for some hints. Thank you in advance for your time. Micha? ~,~`~,~`~,~`~,~`~,~`~,~ Micha? Bojanowski bojaniss at poczta.onet.pl