Analysis of template update strategies for keystroke dynamics
Analysis of template update strategies for keystroke dynamics
复制标题
击键动力学模板更新策略分析
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
C. Rosenberger
中科院分区：
文献类型：
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作者：
R. Giot;B. Dorizzi;C. Rosenberger
击键动态是一种行为生物识别技术，随着时间的推移，性能会下降。这是由于用户在使用系统时改进了他/她的打字方式，因此测试样本可能与在较早阶段计算的初始模板不同。绕过此问题的一种方法是使用模板更新机制。在这项工作中，我们提出了新的半监督更新机制，灵感来自已知的监督。这些方案依赖于两个阈值（接受阈值和更新阈值）的选择，这两个阈值根据系统的性能和更新模板中可能包含冒名顶替者数据的容忍度手动固定。我们还提出了一个新的评估方案的更新机制，考虑到性能的演变在几个时间会话。我们的研究结果表明，在监督计划和45%的半监督的配置的参数选择，使我们不接受许多错误的数据的改进。
Keystroke dynamics is a behavioral biometrics showing a degradation of performance when used over time. This is due to the fact that the user improves his/her way of typing while using the system, therefore the test samples may be different from the initial template computed at an earlier stage. One way to bypass this problem is to use template update mechanisms. We propose in this work, new semi-supervised update mechanisms, inspired from known supervised ones. These schemes rely on the choice of two thresholds (an acceptance threshold and an update threshold) which are fixed manually depending on the performance of the system and the level of tolerance in possible inclusion of impostor data in the update template. We also propose a new evaluation scheme for update mechanisms, taking into account performance evolution over several time-sessions. Our results show an improvement of 50% in the supervised scheme and of 45% in the semi-supervised one with a configuration of the parameters chosen so that we do not accept many erroneous data.