Hi All, I was hoping someone could save me the trouble of reading through source code and answer a quick question of mine regarding poly(). Does the poly() function use a classical orthogonal polynomial series to fit polynomial models, or does poly() generate a unique series of orthogonal polynomials based on the method described in Kennedy and Gentle (1980:342-347). I understand that the aforementioned reference is the source for the recursion used in predict.poly(), but I was a bit confused by the documentation regarding how the orthogonal polynomial series was constructed in the first place. If any of the developers are reading - it would be handy to have the orthogonal polynomial series available as an output of poly(), in addition to the coefficients, if that function is generating a unique series based on the dataset used for the approximation. Thanks to everyone for your time, Chris _________________________________________________________________ [[alternative HTML version deleted]]