Title
A sub-constant improvement in approximating the positive semidefinite Grothendieck problem.
Abstract
Semidefinite relaxations are a powerful tool for approximately solving combinatorial optimization problems such as MAX-CUT and the Grothendieck problem. By exploiting a bounded rank property of extreme points in the semidefinite cone, we make a sub-constant improvement in the approximation ratio of one such problem. Precisely, we describe a polynomial-time algorithm for the positive semidefinite Grothendieck problem -- based on rounding from the standard relaxation -- that achieves a ratio of $2/\pi + \Theta(1/{\sqrt n})$, whereas the previous best is $2/\pi + \Theta(1/n)$. We further show a corresponding integrality gap of $2/\pi+\tilde{O}(1/n^{1/3})$.
Year
Venue
Field
2014
CoRR
Pi,Extreme point,Discrete mathematics,Combinatorics,Combinatorial optimization problem,Positive-definite matrix,Rounding,Tilde,Mathematics,Bounded function
DocType
Volume
Citations 
Journal
abs/1408.2270
0
PageRank 
References 
Authors
0.34
4
2
Name
Order
Citations
PageRank
Roy Frostig134712.25
Sida Wang254144.65