Mild departures from the original scale can change a teacher's odds of being classified high- or low-performing by a factor of 5¶
Claim · All claims
Evidence · 1 study · associationalr?·q2
Currency · newest study 2017 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 2020: 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? Even mild nonlinear transformations of the test scale can multiply the odds that a teacher is labeled high- or low-performing by as much as a factor of 5. → Soland 2017
Evidence¶
Soland 2017¶
Soland, J. (2017). Is teacher value added a matter of scale? The practical consequences of treating an ordinal scale as interval for estimation of teacher effects. Applied Measurement in Education, 30(1), 52–70. https://www.nwea.org/research/publication/is-teacher-value-added-a-matter-of-scale-the-practical-consequences-of-treating-an-ordinal-scale-as-interval-for-estimation-of-teacher-effects/ doi:10.1080/08957347.2016.1247844
q2 · i? · associational · r?
In the re-estimation of teacher value added under transformed scales, the article reports that "even mild departures from the original scale can change a teacher's odds of being considered high- or low-performing by a factor of 5." The factor of 5 is an odds multiplier, not a standardized effect size.
"even mild departures from the original scale can change a teacher's odds of being considered high- or low-performing by a factor of 5"
Discussion¶
Related Claims¶
- Rank orderings of teachers do not change radically under mild scale transformations — related
- Teacher value-added estimates are sensitive to the test scale on which they are computed — a broader claim this one bears on
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
scale-transformation-changes-teacher-classification-odds-factor-5 |
title |
Mild departures from the original scale can change a teacher's odds of being classified high- or low-performing by a factor of 5 |
description |
Mild departures from the original scale can change a teacher's odds of being classified high- or low-performing by a factor of 5 |
status |
review |
evidence_strength |
moderate |
newest_evidence |
2017 |
recheck_by |
2020 |
generated |
by process:wiki-ingest on 2026-10-09 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — soland-2017 |
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