Parameter Redundancy in Covariate Models
The parameter redundancy status of a model with covariates can be determined from the same model without covariates. As outlined in the paper Cole and Morgan (2010, Biometrika). The Maple code is given below:
Publication
Cole, D. J. and Morgan, B. J. T (2010) Parameter Redundancy with Covariates. Biometrika, 97, 1002-1005 Pre-print version of paper