Establishing Likelihood Ratios for Patterned Garment Comparisons from Seam Measurement Data1, 2. Issue 3 (28th March 2013)

• Record Type: Journal Article
• Authors: Johnson, D. B.; Perlin, Victor E.; Rohde, Mitchell M.; Thomas, Alice C.; Luu, Cuong Q.; Chang, Jennifer
• Is Part Of: Journal of forensic sciences. Volume 58:Issue 3(2013)
• Page Start: 631
• Page End: 644
• Publication Date: 2013-03-28
• Subjects: forensic science -- individualization -- patterned garments -- matching -- surveillance -- statistics -- likelihood ratio -- incidence rate; Medical jurisprudence -- Periodicals; Forensic sciences -- Periodicals; Forensic Medicine -- Periodicals; Gerechtelijke geneeskunde; Gerechtelijke chemie; Gerechtelijke psychiatrie; 363.2505
• DOI: 10.1111/1556-4029.12125
• Languages: English
• ISSNs: 0022-1198

Abstract

Abstract: It is often challenging to ascribe an objective measure of confidence for identifications based on surveillance imagery from a crime scene. The present work seeks to address this deficiency in the case of garment comparison evidence by developing a quantitative method for establishing a conservative lower bound on the likelihood ratio (LR) for identifications involving patterned garments. The method is based on statistical analysis of pattern offset measurements taken from a sample of garments of the same type (manufacturer, style, and size) as the seized evidence. The developed analysis framework was demonstrated on different types of garments over a range of modeled surveillance imaging scenarios with variable image quality; the lower bounds on the LRs ranged from approximately 10–1 to over 400–1. The statistical model was tested and validated through a large‐scale empirical study involving both simulated and human observer‐performed garment comparisons.