Archive for January, 2007

Interview with IET Magazine on Voice Biometrics in Phone Banking

Saturday, January 20th, 2007

A few weeks ago I was interviewed by IET Magazine about the application of voice biometrics in financial call centre environments. The article “Look Who’s Talking” by Juan Pablo Conti is now available on the Institute of Engineering and Technology website. The IET is the largest professional engineering society in Europe and the second largest of its type in the world.

The article opens rather spectacularly with the statement by Andrew Moloney, head of international marketing at RSA Security, that innovative, entrepreneurial fraudsters are moving their criminal activities from online banking to phone banking. To counter this new form of fraud, financial institutions increasingly base their security not only on what their customers know or have, but also on what they are. Enter voice biometrics. The author mentions the two publicised cases from the Low Countries that have been covered in previous posts on this weblog: ABN AMRO in The Netherlands and Dexia in Belgium. As frequent readers of this blog know, I have had the pleasure of contributing to the latter project.

Whereas the RSA Security executive non-surprisingly stresses the security aspects, my personal contribution to the IET article focused in on the convenience benefits for customers. In a previous weblog article I explained that from a narrow technology-only view on voice biometrics, a heart-rending trade-off between security and convenience seems inevitable. The real value of the IET article is that Andrew Moloney shows a way out of this dilemma.

Mr. Moloney is quoted saying that there is probably a 10% level of [false] reject rate (my emphasis). Note that this figure means nothing if we don’t know the corresponding false accept rate (FAR). But for the sake of the argument, let’s assume the FAR is at an acceptable level (as defined by the financial institution, based on a policy decision, a given accept/reject threshold and test results). Now, to lower the 10% FRR - indeed unacceptable in large-scale roll-outs - while keeping the FAR at a fixed low level, the RSA Security executive’s strategy of framing the voice biometrics application in a broader security and convenience perspective is absolutely right. Mr. Moloney explains that by looking at a genuine caller’s past usage patterns, it becomes possible to factor in more security-related attributes in the final accept/reject decision. How can this work?

My interpretation is that at first, the pure voice biometrics threshold is lowered. As a result, FRR goes down, while FAR goes up – that’s the name of the trade-off game. But to compensate for this temporary loss of security, the call’s actual (non voice related) attributes are then compared with the expected attributes as learnt from the (assumed) genuine customer’s past usage patterns: filtering out abnormal behaviour brings the FAR down again. In the end, FRR goes down, while FAR is still stable at an acceptable level. So everyone wins.

Reminder: 17th CLIN meeting in Leuven, Belgium

Monday, January 8th, 2007

This Friday Jan 12, 2007 the University of Leuven Centre for Computational Linguistics hosts the 17th CLIN meeting. CLIN (= Computational Linguistics in the Netherlands) brings together (mostly academic) computational linguists from the Netherlands, Flanders (= the Dutch-speaking part of Belgium), and abroad.