Effective speaker spotting for Watch-list detection of fraudsters in telephone banking

Abstract

This study describes a special-case application of speaker recognition in open-set speaker-identification mode, which nonetheless has wide applicability. Watch-list based speaker spotting in telephone banking can potentially provide valuable protection against 'known' fraudsters with access to stolen customer details. In this study, the detection of known fraudsters in a telephone banking service using commercial off-the-shelf verification engines is described. A new 'delta scoring' method for watch-list detection is proposed based on using the genuine customer model as a reference. The approach combines for the first time speaker recognition in both verification and identification mode. Empirical experiment results show a significant gain in performance using the new method.