theta.s {ape}R Documentation

Population Parameter THETA using Segregating Sites in DNA Sequences

Description

This function computes the population parameter THETA using the number of segregating sites s in a sample of n DNA sequences.

Usage

theta.s(s, n, variance = FALSE)

Arguments

s a numeric giving the number of segregating sites.
n a numeric giving the number of sequences.
variance a logical indicating whether the variance of the estimated THETA should be returned (TRUE), the default being FALSE.

Value

a numeric vector of length one with the estimated theta (the default), or of length two if the standard error is returned (variance = TRUE).

Note

The number of segregating sites needs to be computed beforehand, for instance with the function seg.sites (see example below).

Author(s)

Emmanuel Paradis paradis@isem.univ-montp2.fr

References

Watterson, G. (1975) On the number of segragating sites in genetical models without recombination. Theoretical Population Biology, 7, 256–276.

Tajima, F. (1989) Statistical method for testing the neutral mutation hypothesis by DNA polymorphism. Genetics, 123, 585–595.

See Also

theta.h, theta.k, seg.sites, nuc.div

Examples

data(woodmouse)
y <- seg.sites(woodmouse)
s <- length(y)
n <- length(woodmouse)
theta.s(s, n)
theta.s(s, n, variance = TRUE)

[Package ape version 1.7 Index]