Distortion in Social Choice Problems: The First 15 Years and Beyond

TL;DR

This paper surveys 15 years of research on distortion in social choice, analyzing how limited preference information impacts social welfare and discussing open problems and future directions.

Contribution

It provides a comprehensive overview of key results in distortion, highlighting progress, open challenges, and promising research avenues in social choice theory.

Findings

Significant bounds on distortion in various social choice settings

Identification of open problems in the field

Discussion of future research directions

Abstract

The notion of distortion in social choice problems has been defined to measure the loss in efficiency -- typically measured by the utilitarian social welfare, the sum of utilities of the participating agents -- due to having access only to limited information about the preferences of the agents. We survey the most significant results of the literature on distortion from the past 15 years, and highlight important open problems and the most promising avenues of ongoing and future work.