Partial proportional odds model

["Inman, Brant A. M.D." <Inman.Brant@mayo.edu>]

Peterson and Harrell (Appl Stat 1990; 39: 205-17) describe constrained and unconstrained partial proportional odds models for ordinal logistic regression.  I would like to explore these models in a dataset that I am currently working on. 

Does anybody know if these techniques are implemented in a S-Plus library or R package?

Thanks,
Brant

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Dr. Brant A. Inman,  MD FRCSC
Urologic Oncology Fellow, Mayo Clinic College of Medicine
200 First Street SW
Rochester, MN   55905
Phone: (507) 284-1330
Fax:    (507) 284-4951
Email:  inman.brant@mayo.edu
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