title: A more straightforward derivation of the LR for a database search.
abstract: Matching DNA profiles of an accused person and a crime scene trace are one of the most common forms of forensic evidence. A number of years ago the so-called 'DNA controversy' was concerned with how to quantify the value of such evidence. Given its importance, the lack of understanding of such a basic issue was quite surprising and concerning. Deriving the equation for the likelihood ratio of a DNA database match in a much more direct and simple way is the topic of this paper. As it is much easier to follow it is hoped that this derivation will contribute to the understanding.
authors.affiliation: Netherlands Forensic Institute, PO Box 24044, 2490 AA The Hague, The Netherlands; Leiden University, Institute for Criminal Law and Criminology, PO Box 9520, 2300 RA Leiden, The Netherlands. Electronic address: c.berger@nfi.minvenj.nl.
authors.forename: Charles E H
authors.initials: CE
authors.lastname: Berger
authors.affiliation: Netherlands Forensic Institute, PO Box 24044, 2490 AA The Hague, The Netherlands.
authors.forename: Peter
authors.initials: P
authors.lastname: Vergeer
authors.affiliation: Environmental Science & Research Ltd., Private Bag 92021, Auckland 1142, New Zealand.
authors.forename: John S
authors.initials: JS
authors.lastname: Buckleton
mesh_terms: D030541:Databases, Genetic; D053803:Forensic Genetics; D006801:Humans; D016013:Likelihood Functions
keywords: Database search; Evidence interpretation; Forensic DNA; Likelihood ratio