This workshop seeks to raise and answer four questions--

Q1. What is effect size?

Q2. Why reporting effect size?

Q3. When reporting effect size?

Q4. How to report effect size?

Specifically, the content will focus on the following specific topics-- 

• 1. Alternatives effect size (ES) to Cohen’s d to conceptualize ES beyond standardized mean differences

  2. Contrast alternative ES with Cohen’s d in purposes, usages, statistical assumptions, statistical properties, interpretability, and potential for meta-analysis 

  3. A typology of ES for between-subjects designs

  4. ES for within-subjects designs

  5. Kelley and Preacher’s definition for ES

1. Chen, L. T., Peng, C. Y. J. (2013). Constructing Confidence Intervals for Effect Sizes in ANOVA Designs. Journal of Modern Applied Statistical Methods, 12(2), 82-104.

2. Cohen, J. (1962). The Statistical Power of Abnormal-Social Psychological Research: A Review. Journal of Abnormal and Social Psychology, 65(3), 145-153.

3. Kelly, K., Preacher, K. J. (2012). On Effect Size. Psychological Methods, 17(2), 137-152.

4. Olejnik, S., Algina, J. (2000). Measures of Effect Size for Comparative Studies: Applications, Interpretations, and Limitations. Contemporary Educational Psychology, 25, 241–286.

5. Parker, R. I., Vannest, K. J., Davis, J. L. (2011). Effect Size in Single-Case Research: A Review of Nine Nonoverlap Techniques, Behavior Modification, 35(4), 303–322.

6. Peng, C. Y. J., Chen, L. T. (2014). Beyond Cohen’s d--Alternative Effect Size Measures  for Between-Subject Designs. The Journal of Experimental Education, 82(1), 22–50.

7. Peng, C. Y. J., Chen, L. T., Chiang, H. M., Chiang, Y. C. (2013). The Impact of APA and AERA Guidelines on Effect Size Reporting. Educational Psychology Review, 25(2), 157-209.