| Title | : | CSE Bytes -- Bridging the Algebraic and Graph Theoretic Aspects of Learning to Rank |
| Speaker | : | Arun Rajkumar (IITM) |
| Details | : | Fri, 3 Mar, 2023 2:30 PM @ CS 15 |
| Abstract: | : | In this talk, we will discuss the problem of learning to rank from pairwise comparisons. Here the learner is given a set of pairwise comparisons over a set of items and the goal is to aggregate these preferences into a global ranking over the items. Several existing algorithms either implicitly or explicitly make certain algebraic low rank assumptions on the underlying preference model that generates the pairwise data. From a modeling perspective, especially for intransitive preferences, it is important to understand the kind of preference structures (Tournament graph among the items) that these algebraic restrictions correspond to. We initiate a line of work where we hope to bridge the algebraic and graph theoretic aspects of the learning to rank problem. We completely characterise the preference structures (Tournaments) arising out of rank 2 preferences and conjecture on the possible characterisation for higher rank preferences. These conjectures are closely related to the long standing Hadamard conjecture and might be of independent interest. |
