Title
The Complexity of Somewhat Approximation Resistant Predicates.
Abstract
A boolean predicate f : {0, 1}(k) -> {0, 1} is said to be somewhat approximation resistant if for some constant tau > vertical bar f(-1)(1)vertical bar/2(k), given a tau-satisfiable instance of the MAX k-CSP( f) problem, it is NP-hard to find an assignment that strictly beats the naive algorithm that outputs a uniformly random assignment. Let tau( f) denote the supremum over all tau for which this holds. It is known that a predicate is somewhat approximation resistant precisely when its Fourier degree is at least 3. For such predicates, we give a characterization of the hardness gap (tau(f) - vertical bar f(-1)(1)vertical bar/2(k)) up to a factor of O(k(5)). We show that the hardness gap is determined by two factors: The nearest Hamming distance of f to a function g of Fourier degree at most 2, which is related to the Fourier mass of f on coefficients of degree 3 or higher. Whether f is monotonically below g. When the Hamming distance is small and f is monotonically below g, we give an SDP-based approximation algorithm and hardness results otherwise. We also give a similar characterization of the integrality gap for the natural SDP relaxation of MAX k-CSP(f) after Omega(n) rounds of the Lasserre hierarchy.
Year
DOI
Venue
2012
10.1007/978-3-662-43948-7_57
Lecture Notes in Computer Science
DocType
Volume
ISSN
Journal
8572
0302-9743
Citations 
PageRank 
References 
0
0.34
16
Authors
3
Name
Order
Citations
PageRank
Subhash Khot12064112.51
Madhur Tulsiani235824.60
Pratik Worah3518.90