A Framework to Design Approximation Algorithms for Finding Diverse Solutions in Combinatorial Problems

TL;DR

This paper introduces a framework for designing approximation algorithms to find multiple diverse solutions in combinatorial problems, addressing the challenge of solution diversity in real-world applications.

Contribution

It proposes a general framework for approximation algorithms that efficiently find diverse solutions, including constant-factor and PTAS algorithms for various problems.

Findings

Constant-factor approximation algorithms for diverse matchings

PTAS for diverse minimum cuts and interval scheduling

Framework enables systematic design of diverse solution algorithms

Abstract

Finding a \emph{single} best solution is the most common objective in combinatorial optimization problems. However, such a single solution may not be applicable to real-world problems as objective functions and constraints are only "approximately" formulated for original real-world problems. To solve this issue, finding \emph{multiple} solutions is a natural direction, and diversity of solutions is an important concept in this context. Unfortunately, finding diverse solutions is much harder than finding a single solution. To cope with difficulty, we investigate the approximability of finding diverse solutions. As a main result, we propose a framework to design approximation algorithms for finding diverse solutions, which yields several outcomes including constant-factor approximation algorithms for finding diverse matchings in graphs and diverse common bases in two matroids and PTASes for finding diverse minimum cuts and interval schedulings.