HWxtest (version 1.0.5)

acount: Find Approximate Number of Genotype Tables

Description

Use acount to obtain the approximate number of genotype tables for a given set of allele counts. This method uses a normal approximation and is much faster than enumerating the tables with xcount but not as accurate.

Usage

acount(m)

Arguments

m

vector containing the numbers of alleles of each type. Length must be at least 2. All items are positive integers. It can also be a matrix of genotype counts, an object of type genotype, but not a vector of genotype counts.

Value

• The approximate number of tables.

References

The methods are described by http://dx.doi.org/10.1534/genetics.109.108977{Engels, 2009. Genetics 183:1431}.

See Also

hwx.test, xcount

Examples

# Allele counts from human Rh locus. Guo and Thompson, 1992, Figure 1
#
alleles <- c(15, 14, 11, 12, 2, 2, 1, 3)
acount(alleles)
# This approximation may be compared with the exact value of 250552020
#
ld <- c(6329, 319, 47, 2773, 75, 6702, 14, 2, 333)
acount(ld)
#
# This is an example where the number of tables is too large for a full enumeration.