With advances in computerized tests, it has become commonplace to register not just the accuracy of the responses provided to the items, but also the response time. The idea that for each response both response accuracy and response time are indicative of ability has explicitly been incorporated in the signed residual time (SRT) model (Maris & van der Maas, 2012, Psychometrika, 77, 615–633), which assumes that fast correct responses are indicative of a higher level of ability than slow correct responses. While the SRT model allows one to gain more information about ability than is possible based on considering only response accuracy, measurement may be confounded if persons show differences in their response speed that cannot be explained by ability, for example due to differences in response caution. In this paper we propose an adapted version of the SRT model that makes it possible to model person differences in overall speed, while maintaining the idea of the SRT model that the speed at which individual responses are given may be indicative of ability. We propose a two-dimensional SRT model that considers dichotomized response time, which allows one to model differences between fast and slow responses. The model includes both an ability and a speed parameter, and allows one to correct the estimates of ability for possible differences in overall speed. The performance of the model is evaluated through simulation, and the relevance of including the speed parameter is studied in the context of an empirical example from formative educational assessment.

中文翻译：

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考虑离散有符号剩余时间模型中速度的个体差异

随着计算机化测试的进步，不仅记录提供给项目的响应的准确性，而且记录响应时间已经变得司空见惯。对于每个响应，响应准确度和响应时间都表示能力的想法已明确纳入带符号剩余时间 (SRT) 模型 (Maris & van der Maas, 2012, Psychometrika, 77, 615–633)，它假设快速正确的响应比缓慢的正确响应表明更高的能力水平。虽然 SRT 模型允许人们获得比仅考虑响应准确性更多的关于能力的信息，但如果人们表现出无法用能力解释的响应速度差异，例如由于响应谨慎的差异，则测量可能会混淆。在本文中，我们提出了 SRT 模型的改编版本，它可以模拟人在整体速度方面的差异，同时保持 SRT 模型的思想，即给出个人反应的速度可能表明能力。我们提出了一种考虑二分响应时间的二维 SRT 模型，该模型允许对快速响应和慢速响应之间的差异进行建模。该模型包括能力和速度参数，并且允许人们针对整体速度的可能差异来校正能力估计。通过模拟评估模型的性能，并在形成性教育评估的经验示例的背景下研究包括速度参数的相关性。