Skip to main content

The Overestimation of Effect Sizes from F Values in Meta-Analysis: The Cause and a Solution

Buy Article:

$55.00 plus tax (Refund Policy)

Abstract:

Because estimates of effect sizes are often either misreported or not reported at all, meta-analysts must use conversion formulas that allow them to estimate effect sizes from the information available in a research report. The focus of this paper is on formulas that convert F in ANOVA to eta-squared, d, or the correlation coefficient. This paper demonstrates that the traditional F to r formula can differentially, and in some cases radically, inflate estimates of effect size when extracting the results from studies with varying numbers of factors. Specifically, commonly used conversion formulas for converting F values to r actually yield a partial r statistic that can be substantially larger than the desired zero-order r depending upon the number and relevance of additional factors in ANOVA. An alternative method to calculate nonpartialled effect sizes according to the common formula (SSeffect/SStotal) is provided.

Document Type: Research Article

DOI: https://doi.org/10.1080/0363775032000104586

Publication date: 2003-03-01

  • Access Key
  • Free ContentFree content
  • Partial Free ContentPartial Free content
  • New ContentNew content
  • Open Access ContentOpen access content
  • Partial Open Access ContentPartial Open access content
  • Subscribed ContentSubscribed content
  • Partial Subscribed ContentPartial Subscribed content
  • Free Trial ContentFree trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more