naa a22 4500 510777090 CHVBK 20180411083234.0 cr unu---uuuuu 180411e20131201xx s 000 0 eng 10.3758/s13428-013-0392-4 doi (NATIONALLICENCE)springer-10.3758/s13428-013-0392-4 Cumming Geoff Statistical Cognition Laboratory, School of Psychological Science, La Trobe University, 3086, Melbourne, Victoria, Australia aut Cohen's d needs to be readily interpretable: Comment on Shieh (2013) [Elektronische Daten] [Geoff Cumming] Shieh (2013) discussed in detail δ*, a proposed standardized effect size measure for the two-independent-groups design with heteroscedasticity. Shieh focused on inference—notably, the large challenge of calculating confidence intervals for δ*. I contend, however, that the standardizer chosen for δ*, meaning the units in which it is expressed, is appropriate for inference but causes δ* to be inconsistent with conventional Cohen's d. In addition, δ* depends on the relative sample sizes in the particular experiment and, thus, lacks the generality that is highly desirable if a standardized effect size is to be readily interpretable and also usable in meta-analysis. In the case of heteroscedasticity, I suggest that researchers should choose as standardizer for Cohen's δ the best available estimate of the SD of an appropriate population, usually the control population, in preference to δ* as discussed by Shieh. Psychonomic Society, Inc., 2013 Cohen's d nationallicence Standardized mean difference nationallicence Effect sizes nationallicence Interpretation nationallicence Meta-analysis nationallicence Behavior Research Methods Springer US; http://www.springer-ny.com 45/4(2013-12-01), 968-971 45:4<968 2013 45 13428 https://doi.org/10.3758/s13428-013-0392-4 text/html Onlinezugriff via DOI 1 brief-communication jats NATIONALLICENCE 856 40 https://doi.org/10.3758/s13428-013-0392-4 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Cumming Geoff Statistical Cognition Laboratory, School of Psychological Science, La Trobe University, 3086, Melbourne, Victoria, Australia aut NATIONALLICENCE 773 0- Behavior Research Methods Springer US; http://www.springer-ny.com 45/4(2013-12-01), 968-971 45:4<968 2013 45 13428 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer