ERIC Number: EJ1110989
Record Type: Journal
Publication Date: 2009-Dec
Pages: 56
Abstractor: As Provided
ISBN: N/A
ISSN: EISSN-2330-8516
EISSN: N/A
Methods of Linking with Small Samples in a Common-Item Design: An Empirical Comparison. Research Report. ETS RR-09-38
Kim, Sooyeon; Livingston, Samuel A.
ETS Research Report Series, Dec 2009
A series of resampling studies was conducted to compare the accuracy of equating in a common item design using four different methods: chained equipercentile equating of smoothed distributions, chained linear equating, chained mean equating, and the circle-arc method. Four operational test forms, each containing more than 100 items, were used for the equating, with new-form samples of 100, 50, 25, and 10 examinees and reference-form samples three times as large. Accuracy was assessed in terms of the root-mean-squared difference (over 1,000 replications) of the sample equatings from the criterion equating. Overall, chained mean equating produced the most accurate results for low scores, but the circle-arc method produced the most accurate results, particularly in the upper half of the score distribution.
Descriptors: Sampling, Sample Size, Accuracy, Test Items, Equated Scores, Test Construction, Error of Measurement, Comparative Analysis, Ability, Scoring
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A