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

NCJ Number
Forensic Science International-Genetics Volume: 37 Dated: November 2018 Pages: 29-36
Date Published
November 2018
8 pages
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 Published: November 1, 2018