Performance assessment in keystroke dynamics by combined profile documents for free text typing

We have investigated several characteristics of the keystroke dynamics in Japanese free text. In the previous studies, it was indicated that authentication accuracy could not achieve the adequate level of personal authentication for the group including lower typing skill participants. In this paper, we propose a new profiling method generating combined profile documents. By performing a large scale experiment involving 260 participants, we found that the method combining two profile documents out of ten profile documents resulted in the recognition accuracy rate of 98 % even in the case for the group including lower typing skill participants who manage to type 500 to 700 letters per 5 minutes.