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Modelling the Dependence Structure of Y-STR Haplotypes Using Graphical Models

NCJ Number
Date Published
November 2018
8 pages
Mikkel M. Andersen; James Curran; Jacob de Zoete; Duncan Taylor; John Buckleton
Publication Type
Research (Applied/Empirical), Report (Study/Research), Report (Grant Sponsored), Program/Project Description
Grant Number(s)
This article reports on a reconsideration of the problem of population frequency estimation by application of Bayesian networks and the Chow-Liu algorithm to model dependencies between loci.
Many methods have been suggested for evaluating the evidential value of a matching Y-chromosomal DNA profile obtained from a biological stain associated with a crime scene and the Y-chromosomal DNA profile of a suspect. Most of these methods are based on estimating the population frequency of the Y-profile. The common independence assumption between loci for autosomal DNA profiles cannot be used for Y-chromosomal DNA profiles. The study found that the method based on the Chow-Liu algorithm performs almost as well as the discrete Laplace method. The study also made comparisons to the independence model, demonstrating once again that the independence method for Y-profiles cannot be supported. (publisher abstract modified)
Date Created: July 20, 2021