Nial Friel : The Bradley-Terry stochastic block model.
Nial Friel is a Full Professor of Statistics at University College Dublin. He was awarded a PhD in 1999 from the University of Glasgow. Following postdocs at Queensland University of Technology, University of Cambridge, Athens University of Economics and Business, he joined the University of Glasgow as a lecturer in 2002 and was promoted to Reader in 2006. In 2007 he was appointed as a Professor of Statistics at University College Dublin until being promoted to Full Professor of Statistics in 2014, a position which he currently holds. His research interests are in Bayesian Statistics, network analysis, Monte Carlo methods. He served as Joint Editor of the Journal of the Royal Statistical Society, Series B from 2019 to 2022.
Time and place:–,
Erling Sverdrups plass, Niels Henrik Abels hus, 8th floor
The Bradley-Terry model is widely used to model pairwise comparisons between items or teams or objects, depending on the application of interest. A key use of the Bradley-Terry is to rank the items under consideration. Our objective is to embed the Bradley-Terry within a stochastic block framework. In so doing we allow for the possibility that items are clustered. Effectively, items within the same cluster (or block) share the same rank. We employ a Gnedin prior on the space of partitions of items in order to assess the number of blocks. We illustrate our model on over 20 seasons of the ATP men's tennis tour. Our study provides some quantitative insights into the nature of the competitiveness of this competition over time.
Reference: Lapo Santi, Nial Friel. (2026) "The Bradley–Terry stochastic block model."Annals of Applied Statistics20 (2) 1766 - 1787.doi.org/10.1214/26-AOAS2193
