help effectsize
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Title
effectsize --
Computes effect size after anova.
Syntax
effectsize term
options description
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Required
term Anova term being tested
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Description
effectsize computes effects size after anova. The output includes omega2, eta2, Cohen's f, partial omega2, and partial eta2.
Remarks
Eta2 is interpreted as percent of dv accounted for by the effect in the sample. While omega2 is interpreted as percent of dv
accounted for by the effect in the population.
Rough guidelines for effect size:
omega2 and eta2: .01 small; .06 medium; .14 large
Cohen's f: .10 small; .25 medium; .40 large
Of course, these are only very rough guidelines.
Examples
. anova write prog female prog*female
. effectsize prog
. effectsize prog*female
References
(1995) Kirk, R.E. Experimental design: Procedures for the behavioral sciences (3rd ed). Pacific Grove, CA: Brooks/Cole.
(2008) SAS 9.2 Documentation for GLM. Cary, NC: SAS Institute Inc.
Author
Philip B. Ender
UCLA Statistical Consulting Group
ender@ucla.edu
Statistical Methods and Data Analytics
