Hello, are there potential drawbacks in the use of rank (ordinal) variables as predictors in a "linear" mixed model for continuous dependents? I am trying this approach to create mixed effects models independent of the (monotonic) transform of the independent variables. The use of rank transformed independents seems the logical choice to me. Thank you for any feedback, Bruno ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Bruno L. Giordano, Ph.D. CIRMMT Schulich School of Music, McGill University 555 Sherbrooke Street West Montr?al, QC H3A 1E3 Canada http://www.music.mcgill.ca/~bruno/