Performance Evaluation of Biometric Template Update
This work addresses the lack of standardized evaluation in biometric template update, which is crucial for researchers and developers to compare systems effectively, though it is incremental as it identifies a problem without solving it.
The paper highlights that inconsistent evaluation procedures for biometric template update systems lead to contradictory interpretations of results, using keystroke dynamics on an eight-session dataset to demonstrate this issue.
Template update allows to modify the biometric reference of a user while he uses the biometric system. With such kind of mechanism we expect the biometric system uses always an up to date representation of the user, by capturing his intra-class (temporary or permanent) variability. Although several studies exist in the literature, there is no commonly adopted evaluation scheme. This does not ease the comparison of the different systems of the literature. In this paper, we show that using different evaluation procedures can lead in different, and contradictory, interpretations of the results. We use a keystroke dynamics (which is a modality suffering of template ageing quickly) template update system on a dataset consisting of height different sessions to illustrate this point. Even if we do not answer to this problematic, it shows that it is necessary to normalize the template update evaluation procedures.