Phylogenetic information complexity: Is testing a tree easier than finding it?

Mike Steel; Laszlo Szekely; Elchanan Mossel

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arXiv · 0807.1756

Phylogenetic information complexity: Is testing a tree easier than finding it?

Mike Steel·Laszlo Szekely·Elchanan Mossel

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Abstract

Phylogenetic trees describe the evolutionary history of a group of present-day species from a common ancestor. These trees are typically reconstructed from aligned DNA sequence data. In this paper we analytically address the following question: is the amount of sequence data required to accurately reconstruct a tree significantly more than the amount required to test whether or not a candidate tree was the `true' tree? By `significantly', we mean that the two quantities behave the same way as a function of the number of species being considered. We prove that, for a certain type of model, the amount of information required is not significantly different; while for another type of model, the information required to test a tree is independent of the number of leaves, while that required to reconstruct it grows with this number. Our results combine probabilistic and combinatorial arguments.

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Mike Steel, Laszlo Szekely, Elchanan Mossel. 2008-07-10. Phylogenetic information complexity: Is testing a tree easier than finding it?. https://arxiv.org/abs/0807.1756

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