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Measures of effect size

Richardson, John T. E. (1996). Measures of effect size. Behavior Research Methods, Instruments, and Computers, 28(1) pp. 12–22.

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Two different approaches have been used to derive measures of effect size. One approach is based on the comparison of treatment means. The standardized mean difference is an appropriate measure of effect size when one is merely comparing two treatments, but there is no satisfactory analogue for comparing more than two treatments. The second approach is based on the proportion of variance in the dependent variable that is explained by the independent variable. Estimates have been proposed for both fixed-factor and random-factor designs, but their sampling properties are not well understood. Nevertheless, measures of effect size can allow quantitative comparisons to be made across different studies, and they can be a useful adjunct to more traditional outcome measures such as test statistics and significance levels.

Item Type: Journal Item
ISSN: 1532-5970
Academic Unit/School: Learning and Teaching Innovation (LTI) > Institute of Educational Technology (IET)
Learning and Teaching Innovation (LTI)
Research Group: Centre for Research in Education and Educational Technology (CREET)
Item ID: 49901
Depositing User: John T. E. Richardson
Date Deposited: 29 Jun 2017 14:47
Last Modified: 07 Dec 2018 10:53
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