A Family of Dictatorship Tests with Perfect Completeness for 2-to-2 Label Cover
نویسندگان
چکیده
We give a family of dictatorship tests with perfect completeness and low-soundness for 2–to–2 constraints. The associated 2–to–2 conjecture has been the basis of some previous inapproximability results with perfect completeness. However, evidence towards the conjecture in the form of integrality gaps even against weak semidefinite programs has been elusive. Our result provides some indication of the expressiveness and non-triviality of 2–to–2 constraints, given the close connections between dictatorship tests and satisfiability and approximability of CSPs.
منابع مشابه
An Improved Dictatorship Test with Perfect Completeness
A Boolean function f : {0, 1} → {0, 1} is called a dictator if it depends on exactly one variable i.e f(x1, x2, . . . , xn) = xi for some i ∈ [n]. In this work, we study a k-query dictatorship test. Dictatorship tests are central in proving many hardness results for constraint satisfaction problems. The dictatorship test is said to have perfect completeness if it accepts any dictator function. ...
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ورودعنوان ژورنال:
- Electronic Colloquium on Computational Complexity (ECCC)
دوره 24 شماره
صفحات -
تاریخ انتشار 2017