ibs.pairwise.db.exp: Compute expected number of profiles pairs in a database that...
In DNAprofiles: DNA Profiling Evidence Analysis

Description Usage Arguments Details Value See Also Examples

For a database comparison exercise, this function computes the expected number of pairs that match fully or partially at each number of loci in a heterogeneous database.

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ibs.pairwise.db.exp(subpops, fractions = rep(1/length(subpops),
  length(subpops)), N = 2L, ks = c("UN", "FS", "PO"), alpha.w = c(1, 0,
  0))

`subpops`	List with allele frequencies in each subpopulation.
`fractions`	Numeric
`N`	Total size of database.
`ks`	IBD-probabilities for the relations that occur within subpopulations (with probabilities `alpha.w`) and between (with probabilities `alpha.b`). Passed on to `ibdprobs`.
`alpha.w`	Numeric with same length as `ks`. The `i`'th element denotes the probability that a pair of profiles within a subpopulation is related as described by the `i`'th element of `ks`.

When all profiles in the database are compared pairwise, one can count the number of profiles that match fully/partially for each number of loci. Such a procedure is implemented as ibs.pairwise.db. The current function computes the expected value of this matrix. The database can be heterogeneous (consisting of subpopulations with different allele frequencies) and within-subpopulation inbreeding is supported.

Matrix with the expected number of full/partial matches on 0,1,2,... loci in the database.

as.dbcompare

data(freqsNLsgmplus)

# sample small db, make all pairwise comparisons and compute the expected number

N <- 1e3
db <- sample.profiles(N=N,freqs=freqsNLsgmplus)

O <- ibs.pairwise.db(db)
E <- ibs.pairwise.db.exp(subpops = list(freqsNLsgmplus),N = N)

O # observed
E # expected