Odyssey 2010: The Speaker and Language Recognition Workshop

Brno, Czech Republic
28 June 1 July 2010

Estimating the Precision of the Likelihood-Ratio Output of a Forensic-Voice-Comparison System

Geoffrey Stewart Morrison (1), Tharmarajah Thiruvaran, Julien Epps (2)

(1) Australian National University, (2) The University of New South Wales

The issues of validity and reliability are important in forensic science. Within the likelihood-ratio framework for the evaluation of forensic evidence, the log-likelihood-ratio cost (Cllr) has been applied as an appropriate metric for evaluating the accuracy of the output of a forensic-voice-comparison system, but there has been little research on developing a quantitative metric of precision. The present paper describes two procedures for estimating the precision of the output of a forensic-comparison system, a non-parametric estimate and a parametric estimate of its 95% credible interval. The procedures are applied to estimate the precision of a basic automatic forensic-voice-comparison system presented with different amounts of questioned-speaker data. The importance of considering precision is discussed.

Full Paper (PDF)

Bibliographic reference.  Morrison, Geoffrey Stewart / Thiruvaran, Tharmarajah / Epps, Julien (2010): "Estimating the Precision of the Likelihood-Ratio Output of a Forensic-Voice-Comparison System", In Odyssey-2010, paper 012.