Dear Allstaters, Thanks very much to those who replied to my query: "does anyone know where I can find the proof, if any, that the use of the binary logistic regression or the discriminant function gives the same results if the two groups have a normal distribution?" Summary of some of the replies are listed below. references: 1. Efron B. (1975). The efficiency of logistic regression compared to normal discriminant analysis. JASA, 70, 892-98 2. Press SJ, Wilson S. (1978). Choosing between logistic regression and discriminant analysis. JASS, 73, 699-705 books: 1. David Hand's (new) book on classification 2. Try searching the stats literature for Anderson, J.A. best regards Monica Ferraroni %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%