Sensitivity Analysis of a Bayesian Network for Reasoning about Digital Forensic Evidence

Abstract⎯A Bayesian network representing an actual prosecuted case of illegal file sharing over a peer-to-peer network has been subjected to a systematic and rigorous sensitivity analysis. Our results demonstrate that such networks are usefully insensitive both to the occurrence of missing evidential traces and to the choice of conditional evidential probabilities. The importance of this finding for the investigation of digital forensic hypotheses is highlighted. Keywords–Bayesian network; digital forensic investigation; digital evidence; sensitivity analysis. I. INTRODUCTION AND BACKGROUND Bayesian Belief Networks (BBNs) [1] have recently been applied to reasoning about available evidence in digital forensic investigations [2]. BBNs are used t