Integrality gap of the hypergraphic relaxation of Steiner trees: A short proof of a 1.55 upper bound

作     者：Chakrabarty, Deeparnab Koenemann, Jochen Pritchard, David 

作者机构：Ecole Polytech Fed Lausanne CH-1015 Lausanne Switzerland Univ Penn Philadelphia PA 19104 USA Univ Waterloo Waterloo ON N2L 3G1 Canada 

出 版 物：《OPERATIONS RESEARCH LETTERS》 (运筹学快报)

年 卷 期：2010年第38卷第6期

页      面：567-570页

核心收录：

学科分类：1201[管理学-管理科学与工程(可授管理学、工学学位)] 07[理学] 070104[理学-应用数学] 0701[理学-数学] 

主　　题：Hypergraph Integrality gap Randomized algorithm Steiner tree 

摘      要：Recently, Byrka, Grandoni, RothvoBand Sanita gave a 1.39 approximation for the Steiner tree problem, using a hypergraph-based linear programming relaxation. They also upper-bounded its integrality gap by 1.55. We describe a shorter proof of the same integrality gap bound, by applying some of their techniques to a randomized loss-contracting algorithm. (C) 2010 Elsevier B.V. All rights reserved.