SAS.STAT 9.1 Users Guide (Vol. 4)
The GENMOD procedure now forms classification groups using the full formatted length of the CLASS variable levels. Several new full-rank CLASS variable parameterizations are now available: polynomial, orthogonal polynomial, effect, orthogonal effect, reference, orthogonal reference, ordinal, and orthogonal ordinal. The default parameterization remains the same less-than -full-rank parameterization used in previous releases.
Zero is now a valid value for the negative binomial dispersion parameter corresponding to the Poisson distribution. If a fixed value of zero is specified, a score test for overdispersion (Cameron and Trivedi 1998) is computed.
| 9.1 | As an experimental feature, PROC GENMOD now provides model assessment based on aggregates of residuals. |