What Differential Weighting of Subsets of Items Does and Does Not Accomplish: Geometric Explanation. Research Report. ETS RR-14-20

Autor/in	Carlson, James E.
Titel	What Differential Weighting of Subsets of Items Does and Does Not Accomplish: Geometric Explanation. Research Report. ETS RR-14-20
Quelle	In: ETS Research Report Series, (2014), (20 Seiten)Infoseite zur Zeitschrift PDF als Volltext kostenfreie Datei Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	2330-8516
Schlagwörter	Geometric Concepts; Scores; Validity; Reliability; Equations (Mathematics); Test Items; Statistical Analysis; Weighted Scores; Measurement + Suchen Sie Ihr Suchwort? Elementare Geometrie; Gültigkeit; Reliabilität; Equations; Mathematics; Gleichungslehre; Test content; Testaufgabe; Statistische Analyse; Messverfahren
Abstract	A little-known theorem, a generalization of Pythagoras's theorem, due to Pappus, is used to present a geometric explanation of various definitions of the contribution of component tests to their composite. I show that an unambiguous definition of the unique contribution of a component to the composite score variance is present if and only if the component scores are uncorrelated. I further show the effect of differentially weighting the composites on the definitions of unique contributions and discuss some of the implications for composite score reliability and validity. (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2020/1/01