sumstat_four_gamete {coala} | R Documentation |
Summary Statistic: Four-Gamete-Condition
Description
This summary statistic calculates a number of values (see 'Value') related to the Four-Gamete-Condition (see 'Details'). It is sensitive for recombination and particularly useful when estimating recombination rates with jaatha or Approximate Bayesian Computation.
Usage
sumstat_four_gamete(
name = "four_gamete",
population = 1,
transformation = identity,
na.rm = FALSE
)
Arguments
name |
The name of the summary statistic. When simulating a model, the value of the statistics are written to an entry of the returned list with this name. Summary statistic names must be unique in a model. |
population |
The population for which the statistic is calculated. Can also be "all" to calculate it from all populations. Default is population 1. |
transformation |
An optional function for transforming the results of the statistic. If specified, the results of the transformation are returned instead of the original values. |
na.rm |
should missing data be ignored? Default is FALSE. |
Details
The Four-Gamete-Condition for two SNPs is violated if all four combinations of derived and ancestral alleles at the SNPs are observed in a gamete/a haplotype. Under an Infinite-Sites mutation model, a violation indicates that there must have been at least one recombination event between the SNPs.
Value
The statistic generates a matrix where each row represents one locus, and the columns give the statistic for different classes of pairs of SNPs:
- mid_near
The value for all pairs of SNPs that are close together, that is within 10 percent of the locus" length. If locus trios are used, only pairs of SNPs were both SNPs are on the middle locus are considered.
- mid_far
Same as
mid_near
, but for pairs of SNPs that are more that 10 percent of the locus" length apart.- outer
Only when using locus trios. The statistic for pairs where both SNPs are on the same outer locus.
- between
Only when using locus trios. The statistic for pairs where one SNPs is on the middle locus, and the other is on an outer one.
- mid
The value for all pairs on the middle locus or all pairs when not using trios.
- perc_polym
The percentage of positions that are polymorpic.
Unphased Data
For unphased data, the four gamete condition is only counted as violated if it is violated for all possible phasing of the data.
See Also
To create a demographic model: coal_model
To calculate this statistic from data: calc_sumstats_from_data
Other summary statistics:
sumstat_dna()
,
sumstat_file()
,
sumstat_ihh()
,
sumstat_jsfs()
,
sumstat_mcmf()
,
sumstat_nucleotide_div()
,
sumstat_omega()
,
sumstat_seg_sites()
,
sumstat_sfs()
,
sumstat_tajimas_d()
,
sumstat_trees()
Examples
model <- coal_model(5, 2) +
feat_mutation(50) +
feat_recombination(10) +
sumstat_four_gamete()
stats <- simulate(model)
print(stats$four_gamete)