The Bradley-Terry-Luce (BTL) model is well-known in the literature on discrete choice (Bradley & Terry, 1952). It starts from the parametric model of pairwise comparisons:
Given n x n matrix C of pairwise comparisons, where C[i,j] informs about how often the item x_i wins over x_j, the parameters
can be estimated by likelihood maximization:
the implementation of which is placed in BTL.py. Check out this work for more details.