English

The existence of maximum likelihood estimates in the Bradley-Terry model and its extensions

Statistics Theory 2007-06-13 v1 Statistics Theory

Abstract

In the Bradley-Terry model for paired comparisons, and its extensions to include order effects and ties, the maximum likelihood estimates of probabilities of certain outcomes can be 0 or 1 under certain data configurations. This poses problems for standard estimation methods. In this paper, we give algorithms for identifying the outcomes with estimated probability 0 or 1, and indicate how the remaining probabilities may be estimated and summarized.

Keywords

Cite

@article{arxiv.math/0412232,
  title  = {The existence of maximum likelihood estimates in the Bradley-Terry model and its extensions},
  author = {Kenneth Butler and John T. Whelan},
  journal= {arXiv preprint arXiv:math/0412232},
  year   = {2007}
}

Comments

27 pages, LaTeX; later version of Dalhousie University Technical Report DALTR-00-1