ABSTRACT
Raw responses to the items in an ability test typically have the physical form of bubbles on an answer sheet, clicks with a computer mouse, or a few lines of text. Each of these responses has two important aspects: (i) its degree of correctness and (ii) the time used to produce it. The former is usually recorded on a numerical scale, typically a 0–1 scale for incorrect–correct responses or a more-refined scale for the evaluation of polytomous items. Until recently, response times (RTs) on items could be recorded only for individually proctored tests. But since the arrival of computers and handheld electronic devices in testing, they have become automatically available for any type of test.
