simLRprelim {mispitools}

Simulate likelihoods ratio (LRs) based on preliminary investigation data: a function for obtaining expected LRs under relatedness and unrelatedness kinship hypothesis.

Description

Simulate likelihoods ratio (LRs) based on preliminary investigation data: a function for obtaining expected LRs under relatedness and unrelatedness kinship hypothesis.

Usage

simLRprelim(
  vartype,
  numsims = 1000,
  seed = 123,
  int = 5,
  ErrorRate = 0.05,
  alphaBdate = c(1, 4, 60, 11, 6, 4, 4),
  numReg = 6,
  MP = NULL,
  database,
  cuts = c(-120, -30, 30, 120, 240, 360)
)

Arguments

vartype

Indicates type of preliminary investigation variable. Options are: sex, region, age, birthDate and height.

numsims

Number of simulations performed.

seed

Seed for simulations.

int

Interval parameter, used for height and age vartypes. It defines the estimation range, for example, if MP age is 55, and int is 10, the estimated age range will be between 45 and 65.

ErrorRate

Error rate for sex, region, age and Height LR calculations.

alphaBdate

Vector containing alpha parameters for Dirichlet distribution. Usually they are the frequencies of the solved cases in each category.

numReg

Number of regions present in the case.

MP

Introduce the preliminary data of the selected variable (vartype) of the MP. If it is null, open search is carried out. If it is not NULL, close search LR is computed. Variables values must be named as those presented in makePOIprelim function.

database

It is used when the close search (MP not NULL), is carried out. It could be the output from makePOIprelim or a database with the same structure.

cuts

Value of differences between DBD and ABD used for category definition. They must be the same as the ones selected for alphaBdate vector.

Value

An object of class data.frame with LRs obtained for both hypothesis, Unrelated where POI/UHR is not MP or Related where POI/UHR is MP.

Examples

library(mispitools) 
simLRprelim("sex")