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The Reliability of Linearly Equated Tests

Published online by Cambridge University Press:  01 January 2025

Daniel O. Segall*
Affiliation:
Navy Personnel Research and Development Center
*
Requests for reprints should be sent to Daniel O. Segall, Code 12, Navy Personnel Research and Development Center, 53335 Ryne Road, San Diego, CA 92152-7250.

Abstract

An asymptotic expression for the reliability of a linearly equated test is developed using normal theory. The reliability is expressed as the product of two terms, the reliability of the test before equating, and an adjustment term. This adjustment term is a function of the sample sizes used to estimate the linear equating transformation. The results of a simulation study indicate close agreement between the theoretical and simulated reliability values for samples greater than 200. Findings demonstrate that samples as small as 300 can be used in linear equating without an appreciable decrease in reliability.

Type
Original Paper
Copyright
Copyright © 1994 The Psychometric Society

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Footnotes

The work reported in this paper was sponsored by the Office of Naval Research Exploratory Development Program in Manpower and Personnel Technology. The author wishes to thank the three anonymous reviewers for their useful comments on an earlier version of this manuscript. The opinions expressed in this article are those of the Author, are not official and do not necessarily reflect the views of the Navy Department.

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