calibrate.set {comparison}

Calculate the calibrated set of idea LRs

Description

Calculates and returns the calibrated set of ⁠ideal' LRs from the observed LRs using the penalised adjacent violators algorithm. This is very much a rewrite of Nico Brummer's ⁠optloglr()' function for Matlab.

Usage

calibrate.set(
  LR.ss,
  LR.ds,
  method = c("raw", "laplace"),
  ties = c("none", "primary", "secondary", "tertiary")
)

Arguments

LR.ss

a vector of likelihood ratios for the comparisons of items known to be from the same source

LR.ds

a vector of likelihood ratios for the comparisons of items known to be from different sources

method

the method used to perform the calculation, either "raw" or "laplace"

ties

method to solve ties in the predictors list, either "none" (not solved) or "primary", "secondary" or "tertiary" (passed to the isotone::gpava() function)

Details

This is an internal function, and is not meant to be called directly. However it has been exported just in case.

Value

a list with two items:

LR.cal.ss

calibrated LRs for the comparison for same set

LR.cal.ds

calibrated LRs for the comparison for different set

Author(s)

David Lucy

References

Ramos, D. & Gonzalez-Rodriguez, J. (2008) Cross-entropy analysis of the information in forensic speaker recognition; IEEE Odyssey.

de Leeuw, J. & Hornik, K. & Mair, P., (2009), Isotone Optimization in R: Pool-Adjacent-Violators Algorithm (PAVA) and Active Set Methods, https://www.jstatsoft.org/article/view/v032i05

See Also

isotone::gpava(), calc.ece()