Polychotomously scored IF-AT physics exam items show excellent discrimination, with a mean item-total correlation of r′ = 0.41 ± 0.13 across 45 items¶

Claim · All claims
Evidence · 1 study · design r2 · q2 · i2 medium
Currency · newest study 2013 · checked against its sources 2026-10-20 (automated, 1 of 1 entry) · not reviewed by a person · overdue for a recheck since 2016: tool and model accuracy changes quickly

Subclaims¶

q2 i? Across a midterm and final exam administered with the IF-AT in an introductory physics course, the 45 polychotomously scored items had a mean item-total correlation of r′ = 0.41 ± 0.13, which the author characterizes as excellent discrimination for classroom tests. → Slepkov 2013

Evidence¶

Slepkov 2013¶

Slepkov, A. D. (2013). Integrated Testlets and the Immediate Feedback Assessment Technique. https://arxiv.org/abs/1308.4365 doi:10.48550/arxiv.1308.4365

q2 · i2 · design · r2

Item analysis of one case-study course's IF-AT-scored midterm (20 items, 51 students) and final (25 items, 49 students). The author reports "excellent discrimination" with mean polychotomous item-total correlation r′ = 0.41 ± 0.13; only 4 of 45 items fell below a discrimination coefficient of 0.2.

"In total, the polychotomously-scored items are found to allow for excellent discrimination, with a mean item-total correlation measure for the combined 45 items of the two examinations of r′ = 0 . 41 ± 0. 13 (mean ± standard deviation)"

Discussion¶

Related Claims¶

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