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ERIC Number: EJ174782
Record Type: CIJE
Publication Date: 1977
Pages: N/A
Abstractor: N/A
Reference Count: 0
ISBN: N/A
ISSN: N/A
The Reliability of Difference Scores When Errors are Correlated
Williams, Richard H.; Zimmerman, Donald W.
Educational and Psychological Measurement, 37, 3, 679-89, Aut 77
The usual formulas for the reliability of differences between two test scores are based on the assumption that the error scores are uncorrelated. Formulas are presented for the general case where this assumption is unnecessary. (Author/JKS)
Descriptors: Correlation, Error of Measurement, Error Patterns, Scores, Test Reliability, True Scores
Publication Type: N/A
Education Level: N/A
Audience: N/A
Language: N/A
Sponsor: N/A
Authoring Institution: N/A
Identifiers: Difference Scores