Scaling is a sine qua non for experimental use of tests, and unscaled tests interpreted as scaled do harm¶

Claim · All claims
Evidence · 1 study · theoretical r2 · q2
Currency · newest study 1921 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? Equal-scale-unit comparability is essential for most experimental purposes because progress along a scale is generally involved; in many situations no test at all does less harm than an unscaled test whose scores are interpreted as though scaled. → Franzen 1921

Evidence¶

Franzen 1921¶

Franzen, R., & Knight, F. B. (1921). Criteria to Employ in Choice of Tests. The Journal of Educational Psychology. https://doi.org/10.1037/h0075312

q2 · i? · theoretical · r2

Analytical argument that equal units across the scale enable comparing progress, which underlies comparison, experiment, classification, diagnosis and quantitative definition. The authors add that teachers and administrators generally misinterpret unscaled scores as scaled; no empirical data reported.

"it is a sine qua non in the use of a test for most experimental purposes, since progress along a scale is generally involved. If we cannot compare progress, and we cannot unless a test is scaled, then we cannot gain much from comparison, experiment, classification, diagnosis or quantitative definition."

Discussion¶

Related Claims¶

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