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arXiv · 1504.01311

PTAS for MAP Assignment on Pairwise Markov Random Fields in Planar Graphs

Eli Fox-Epstein·Roie Levin·David Meierfrankenfeld
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Abstract

We present a PTAS for computing the maximum a posteriori assignment on Pairwise Markov Random Fields with non-negative weights in planar graphs. This algorithm is practical and not far behind state-of-the-art techniques in image processing. MAP on Pairwise Markov Random Fields with (possibly) negative weights cannot be approximated unless P = NP, even on planar graphs. We also show via reduction that this yields a PTAS for one scoring function of Correlation Clustering in planar graphs.

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Eli Fox-Epstein, Roie Levin, David Meierfrankenfeld. 2015-04-06. PTAS for MAP Assignment on Pairwise Markov Random Fields in Planar Graphs. https://arxiv.org/abs/1504.01311

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