delta {introgress}R Documentation

Delta

Description

This function calculates delta (delta), the differential between allelic frequencies in two populations. It is called by the function prepare.data.

Usage

delta(SpA, SpB)

Arguments

SpA a vector of population allele frequencies.
SpB a vector of population allele frequencies.

Details

This function calculates the allele frequency differential for a pair of species or populations (delta, Gregorius and Roberds 1986) for a single locus.

delta = sigma(|f_i1 - f_i2|/2)

where f_{i1} and f_{i2} denote the frequency of the ith allele in populations one and two, respectively. delta ranges from 0, for identical populations, to 1, for populations that share no alleles in common.

Value

This function returns a vector of length one with the value of delta.

Author(s)

Zachariah Gompert zgompert@uwyo.edu, C. Alex Buerkle buerkle@uwyo.edu

References

Gregorius, H. R. and Roberds, J. H. (1986) Measurement of genetical differentiation among subpopulations. Theoretical and Applied Genetics, 71, 826-834.

See Also

prepare.data

Examples

## allele frequencies for two populations
pop.a<-c(0.3,0.5,0.2)
pop.b<-c(0.1,0.1,0.8)

## delta calculation
delta(pop.a,pop.b)

[Package introgress version 1.1 Index]