Ranking-Based Voting Revisited: Maximum Entropy Approach Leads to Borda Count (and Its Versions)

Authors

Olga Kosheleva, The University of Texas at El PasoFollow
Vladik Kreinovich, The University of Texas at El PasoFollow
Guo Wei, University of North Carolina at PembrokeFollow

Publication Date

7-2019

Comments

Technical Report: UTEP-CS-19-70

Abstract

In many practical situations, we need to make a group decision that takes into account preferences of all the participants. Ideally, we should elicit, from each participant, a full information about his/her preferences, but such elicitation is usually too time-consuming to be practical. Instead, we only elicit, from each participant, his/her ranking of different alternatives. One of the semi-heuristic methods for decision making under such information is Borda count, when for each alternative and each participant, we count how many alternatives are worse, and then select the alternatives for which the sum of these numbers is the largest. In this paper, we explain the empirical success of the Borda count technique by showing that this method naturally follows from the maximum entropy approach -- a natural approach to decision making under uncertainty.