NotesFAQContact Us
Collection
Advanced
Search Tips
Author
Levy, Kenneth J.4
Education Level
Audience
Location
Laws, Policies, & Programs
Assessments and Surveys
What Works Clearinghouse Rating
Showing all 4 results Save | Export
Peer reviewed Peer reviewed
Levy, Kenneth J. – Psychometrika, 1975
The Z-variance and Box-Scheffe tests for homogeneity of variance are both relatively simple to perform and readily utilized in complex, multi-factor designs. The Z-variance test is not robust against non-normality; the Box-Scheffe test is robust against non-normality but is not nearly as powerful as the Z-variance test. (Author/BJG)
Descriptors: Analysis of Variance, Comparative Analysis, Hypothesis Testing
Peer reviewed Peer reviewed
Levy, Kenneth J. – Educational and Psychological Measurement, 1975
Proposes three different multiple range tests based upon the Newman-Keuls philosophy with respect to significance levels. The three tests utilize the Fmax statistic, Cochran's statistic and a normalizing log transformation of the sample variances respectively. (Author/RC)
Descriptors: Analysis of Variance, Comparative Analysis, Hypothesis Testing, Statistical Significance
Peer reviewed Peer reviewed
Levy, Kenneth J. – Educational and Psychological Measurement, 1975
The Dunnett procedure for comparing several treatment means with a control is applied to the problem of comparing several treatment variances with the variance of a control. Appropriate critical values are specified and an example is provided. (Author)
Descriptors: Analysis of Variance, Comparative Analysis, Control Groups, Experimental Groups
Peer reviewed Peer reviewed
Levy, Kenneth J. – Journal of Experimental Education, 1978
Monte Carlo techniques were employed to compare the familiar F-test with Welch's V-test procedure for testing hypotheses concerning a priori contrasts among K treatments. The two procedures were compared under homogeneous and heterogeneous variance conditions. (Author)
Descriptors: Analysis of Variance, Comparative Analysis, Hypothesis Testing, Monte Carlo Methods