Randomized Approximation Algorithms

نویسندگان

  • Anupam Gupta
  • Don Sheehy
چکیده

We have seen several randomized approximation algorithms before. Recall that for the MAXCUT and MAX-3SAT problems we proved that choosing any solution uniformly at random gives a constant factor approximation in the expectation. For MAX-CUT the approximation factor was 2. For MAX-3SAT, a random assignment of truth values to a variable satisfies a given clause with probability 78 . In the case of MAX-3SAT, it is possible to derandomize the algorithm and get a deterministic performance guarantee of 87 . Furthermore, this approximation is tight as it has been shown that finding a better approximation is NP-Hard.

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تاریخ انتشار 2005