The weight of a DNA mixture at one locus for one account of who
contributed against another. Each account names the alleles of the
mixture its known contributors do not explain and the number of unknown
contributors who must explain them. Peak heights, drop-out and coancestry
are not modelled. See proof("mixlr").
Arguments
- p
The population frequencies of the alleles in the mixture: named
numbers above 0 with a sum of at most 1.
- np, nd
The alleles left unexplained under the first and the second
account: names of p (or character(0)), at most 20.
- xp, xd
The number of unknown contributors under each account.
Value
A named numeric vector: num, den and lr.
Details
With no alleles to explain and one unknown, the denominator is the chance
a random person is not excluded from the mixture.
References
Weir, B. S., Triggs, C. M., Starling, L., Stowell, L. I.,
Walsh, K. A. J. and Buckleton, J. (1997). Interpreting DNA mixtures.
Journal of Forensic Sciences, 42(2), 213-222.
Examples
# victim explains a and b; suspect would explain c and d
p <- c(a = 0.1, b = 0.2, c = 0.05, d = 0.15)
mixlr(p, np = character(0), xp = 0, nd = c("c", "d"), xd = 1)
#> num den lr
#> 1.00000 0.01500 66.66667
