Robust Z procedure flagged between 4.2% and 6.9% of MAP Growth items as unstable across subjects¶

Claim · All claims
Evidence · 1 study · associational r2 · q2
Currency · newest study 2022 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 2025: tool and model accuracy changes quickly

Subclaims¶

q2 i? Between 4.2% and 6.9% of items across subjects were flagged as unstable by the Robust Z procedure, exceeding or near the 5% nominal error rate except in science. → He 2022

Evidence¶

He 2022¶

He, W. (2022). MAP Growth item parameter drift study. NWEA Research Report. https://www.nwea.org/research/publication/map-growth-item-parameter-drift-study/

q2 · i? · associational · r2

Robust Z analysis (two-sided tests, significance level 0.05) of difficulty differences from two calibrations separated by at least four years. The report states the percentages, except for science items, are slightly larger than the 5% nominal error rate, suggesting some drift occurring on each scale.

"As shown in Table 3.2, between 4.2% and 6.9% of items across subjects were flagged as unstable by the Robust Z procedure."

Discussion¶

Related Claims¶

• Flagged items showed no clear pattern by original difficulty, spreading across the entire scale like unflagged items — related
• 13%–15% of MAP Growth items per subject were flagged as significantly drifted by the Robust Z procedure, with no clear pattern among flagged items — reports the opposite
• Both item-level and test-level analyses indicate the MAP Growth measurement scales are remaining stable — possibly the same claim (merge candidate)