A Procedure for Estimating the Conditional Standard Errors of Measurement for GRE General and Subject Tests

Author(s):
Cowell, William R.
Publication Year:
1991
Report Number:
RR-91-25
GREB-87-03P
Source:
Document Type:
Subject/Key Words:
Error of measurement test reliability

Abstract

A series of computer programs were written for computing the conditional standard errors of measurement (CSEM) for both rights- scored and formula-scored tests based on a method suggested in Lord (1984), commonly known as Lord's Method IV or the compound binomial method. These programs estimate the conditional standard errors of measurement for both raw and scaled scores, average results for two or more forms, and compute form-to-form difference statistics for pairs of forms. Conditional standard errors of measurement, averages, and differences have been computed for the verbal, quantitative, and analytical raw and converted scores for eight forms of the GRE General Test and for two forms each of 15 GRE Subject Tests. The Standards for Educational and Psychological Testing (Committee of AERA, APA, & NCME to Develop Standards, 1985) recommends that test publishers provide estimates of the standard error of measurement at a number of widely spaced score levels. The CSEM data produced in this study have been made available to three programs which use GRE scores, along with other criteria, for awarding fellowships. These data also have been made available for use in GRE program publications and in correspondence.

Read More