English

An Improved Integrality Gap for Steiner Tree

Data Structures and Algorithms 2023-09-12 v9

Abstract

A promising approach for obtaining improved approximation algorithms for Steiner tree is to use the bidirected cut relaxation (BCR). The integrality gap of this relaxation is at least 36/3136/31, and it has long been conjectured that its true value is very close to this lower bound. However, the best upper bound for general graphs was an almost trivial 22. We improve this bound to 3/23/2 by a combinatorial algorithm based on the primal-dual schema.

Keywords

Cite

@article{arxiv.1704.08680,
  title  = {An Improved Integrality Gap for Steiner Tree},
  author = {Ali Çivril and Muhammed Mirza Biçer and Berkay Tahsin Tunca and Muhammet Yasin Kangal},
  journal= {arXiv preprint arXiv:1704.08680},
  year   = {2023}
}
R2 v1 2026-06-22T19:30:08.156Z