You might also want to consider computing the pseudoinverse (also known as generalized inverse, or Moore-Penrose inverse) of the singular matrix. It is a standard repertoire in good numeric libraries, and slightly less ad-hoc than adding fudge factors.
Aleks Jakulin University of Ljubljana . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
