# TOP

Two-stage polytomous logistic regression (TOP): in this package, we developed a two-stage polytomous regression framework to handle cancer data with multivariate tumor characteristics. In the first stage, a standard polytomous model is used to specify for all subtypes defined by the cross-classification of different markers. In the second stage, the subtype-specific case-control odds ratios are specified using a more parsimonious model based on the case-control odds ratio for a baseline subtype, and the case-case parameters associated with tumor markers. Further, to reduce the degrees-of-freedom, we allow to specify case-case parameters for additional markers using a random-effect model.

##### Haoyu Zhang
###### Earl Stadtman tenure-track investigator

My research interests include statistical genetics, causal mediation analysis and risk prediction.