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Peer reviewed Peer reviewed
ERIC Number: EJ571222
Record Type: CIJE
Publication Date: 1998
Pages: N/A
Abstractor: N/A
Reference Count: 0
ISBN: N/A
ISSN: ISSN-0013-1644
To Trim or Not To Trim: Tests of Location Equality under Heteroscedasticity and Nonnormality.
Lix, Lisa M.; Keselman, H. J.
Educational and Psychological Measurement, v58 n3 p409-29 Jun 1998
Comparison of six procedures to test for location equality among two or more groups when population variances are heterogeneous suggests that, when the variance homogeneity and normality assumptions are not satisfied, and the design is unbalanced, the use of any of these test statistics with the usual least squares estimators is not recommended. (SLD)
Descriptors: Comparative Analysis, Estimation (Mathematics), Least Squares Statistics, Research Design
Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers: Equality (Mathematics); Heteroscedasticity (Statistics); Nonnormal Distributions; Trimmed Means; Type I Errors; Variance (Statistical)
Note: Research supported by National Sciences and Engineering Research Council of Canada Grant OGP0015855.