BradleyTerry2 is a package for the R statistical computing environment, designed to facilitate the specification and fitting of Bradley-Terry models for pair comparison data, including structured versions where there are explanatory variables predicting the latent "ability" (or "worth") parameters.
The authors are Heather Turner and David Firth.Some information about the package:
- Overview of BradleyTerry2 (PDF)
- Slides (PDF) for a talk given at the 2nd Workshop on Psychometric Computing, Munich, February 2010.
The package sources, and windows binary, are available at CRAN sites for installation into R in the standard way.
The BradleyTerry2 software is made available free, under GPL version 2. It comes with ABSOLUTELY NO WARRANTY.
This package is a substantial development of the earlier BradleyTerry package, which is now obsolete. The user interface of BradleyTerry2 is different (and much more general), hence the need to change the name of the package.
0.9-1: initial release to CRAN (2010-02-23)
Subsequently maintained and developed as a project at R-forge