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arXiv · 2508.08643

Analytics of Adaptive Online Testing in Practice Over a Decade

Hideo Hirose
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Abstract

Adaptive online testing efficiently assesses examinee proficiency by dynamically adjusting the difficulty of test items based on their performance. To achieve this, items are selected so that their difficulty closely matches the test taker's estimated ability at each stage of the test. This alignment implies that the probability of a correct answer tends toward 0.5. However, in practical settings, this probability may not converge to 0.5 unless the test comprises a sufficiently large number of items. This could give the impression that the adaptive mechanism is not functioning properly. Nevertheless, even when the number of items is small, such as 5 or 7, the adaptive nature of the system can still be observed by examining the relationship between item difficulty and the mean estimated ability of examinees for the corresponding item. Considering that each item typically requires about 2-5 minutes to solve, this number of items appears to be a practical choice that avoids excessive fatigue for test-takers.

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Hideo Hirose. 2025-08-12. Analytics of Adaptive Online Testing in Practice Over a Decade. https://arxiv.org/abs/2508.08643

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