Learning Polytrees

Sanjoy Dasgupta

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arXiv · 1301.6688

Learning Polytrees

Sanjoy Dasgupta

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Abstract

We consider the task of learning the maximum-likelihood polytree from data. Our first result is a performance guarantee establishing that the optimal branching (or Chow-Liu tree), which can be computed very easily, constitutes a good approximation to the best polytree. We then show that it is not possible to do very much better, since the learning problem is NP-hard even to approximately solve within some constant factor.

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Sanjoy Dasgupta. 2013-01-23. Learning Polytrees. https://arxiv.org/abs/1301.6688

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