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arXiv · 2103.00335

Expectation of the Site Frequency Spectrum

Alan R. Rogers·Stephen P. Wooding
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Abstract

The site frequency spectrum describes variation among a set of n DNA sequences. Its i'th entry (i=1,2,...,n-1) is the number of nucleotide sites at which the mutant allele is present in i copies. Under selective neutrality, random mating, and constant population size, the expected value of the spectrum is well known but somewhat puzzling. Each additional sequence added to a sample adds an entry to the end of the expected spectrum but does not affect existing entries. This note reviews the reasons for this behavior.

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Alan R. Rogers, Stephen P. Wooding. 2021-02-27. Expectation of the Site Frequency Spectrum. https://arxiv.org/abs/2103.00335

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