Using Bayesian Networks for Paternity Calculations: Adding an Evolutionary Perspective

• Activity Number: 104
• Type: Topic Contributed
• Date/Time: Monday, August 9, 2004 : 10:30 AM to 12:20 PM
• Sponsor: Biometrics Section
• Author(s): Amanda Hepler*+
• Companies: North Carolina State University
• Keywords: paternity index ; Bayesian networks ; forensic science ; evolution ; evidence interpretation ; subpopulation effects

Abstract

This study expands the current use of Bayesian networks in the forensic setting by incorporating evolutionary effects into paternity calculations. Bayesian networks are gaining popularity as a graphical tool to communicate complex probabilistic reasoning required in the evaluation of DNA evidence. Features of HUGIN (a software package used to create Bayesian networks) are demonstrated that have not, as yet, been explored. These features greatly simplify the process of building Bayesian networks, allowing researchers to use these networks to solve new, more complex problems. Due to the increasing use of DNA evidence in courtrooms, and in light of recent studies on the potential impacts of ignoring evolution, this study is a natural extension to the body of research that already exists on Bayesian networks. We explore three paternity examples, a simple case with two alleles, a simple case with multiple alleles, and a missing father case. Networks are built for each example which incorporate the effects of evolutionary relatedness. We then compare these new networks to previous networks.