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Title: Lasserre Integrality Gaps for Graph Spanners and Related Problems
There has been significant recent progress on algorithms for approximating graph spanners, i.e., algorithms which approximate the best spanner for a given input graph. Essentially all of these algorithms use the same basic LP relaxation, so a variety of papers have studied the limitations of this approach and proved integrality gaps for this LP. We extend these results by showing that even the strongest lift-and-project methods cannot help significantly, by proving polynomial integrality gaps even for n^{\Omega(\epsilon)} levels of the Lasserre hierarchy, for both the directed and undirected spanner problems. We also extend these integrality gaps to related problems, notably Directed Steiner Network and Shallow-Light Steiner Network.  more » « less
Award ID(s):
1909111
PAR ID:
10295388
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
International Workshop on Approximation and Online Algorithms (WAOA)
Page Range / eLocation ID:
97-112
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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