New and old fit statistics are highly correlated after difficulty adjustment, with outfit correlations near 0.99 for Mathematics and infit correlations around 0.7 for Mathematics and mid-to-high 0.8–0.9 for Reading¶
Claim · All claims
Evidence · 1 study · associationalr2·q2
Currency · newest study 2020 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 2023: tool and model accuracy changes quickly
Subclaims¶
Reading the evidence codes
q is the design tier, i the impact, n the sample, and the kind with its r
the rigour judged within that kind: what each code means.
This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.
q2 i? Pearson correlations between new and old outfit statistics reach 0.99 for Mathematics in both samples, while new–old infit correlations are around 0.7 for Mathematics and 0.85 for Reading. → He 2020
Evidence¶
He 2020¶
He, W. (2020). MAP Growth K–2 item fit analysis: A follow-up study. NWEA. https://www.nwea.org/research/publication/map-growth-k-2-item-fit-analysis-study-a-follow-up-study/
q2 · i? · associational · r2
Pearson correlation coefficients between new and old fit statistics (Table 2.1) computed for the AllYr and LatestYr samples; Reading infit correlations are reported as "between the mid to high 0.8-0.9 range."
"For Mathematics, the correlations between the new and the old infit statistics for both samples are around 0.7 (i.e., moderately correlated), whereas the correlations between the new and the old outfit statistics were as high as 0.99."
Discussion¶
Related Claims¶
- Adjusting MAP Growth K–2 item difficulties in the 2020 scale alignment study improved item fit, with the largest gains in outfit statistics for difficult Mathematics items — related
- Item fit findings were the same regardless of whether the AllYr or LatestYr response sample was used — related
- New and old fit statistics are moderately correlated, with Pearson coefficients mostly between 0.50 and 0.79 — reports the opposite
- Mathematics items showed more variation in fit statistics than Reading items, and outfit statistics varied more than infit statistics — related
- Point measure correlations were unchanged by the difficulty adjustment because the new person ability estimates are linear transformations of the old ones — related
- Adjusting MAP Growth K–2 item difficulties improved item fit, with old infit and outfit statistics more scattered than new ones in both samples — related
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
map-k2-new-old-fit-statistic-correlations |
title |
New and old fit statistics are highly correlated after difficulty adjustment, with outfit correlations near 0.99 for Mathematics and infit correlations around 0.7 for Mathematics and mid-to-high 0.8–0.9 for Reading |
description |
New and old fit statistics are highly correlated after difficulty adjustment, with outfit correlations near 0.99 for Mathematics and infit correlations around 0.7 for Mathematics and mid-to-high 0.8–0.9 for Reading |
status |
review |
evidence_strength |
moderate |
newest_evidence |
2020 |
recheck_by |
2023 |
generated |
by process:wiki-ingest on 2026-10-08 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — he-2020 |
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