Abstract
Research in fields other than education has found that studies with small sample sizes tend to have larger effect sizes than those with large samples. This article examines the relationship between sample size and effect size in education. It analyzes data from 185 studies of elementary and secondary mathematics programs that met the standards of the Best Evidence Encyclopedia. As predicted, there was a significant negative correlation between sample size and effect size. The differences in effect sizes between small and large experiments were much greater than those between randomized and matched experiments. Explanations for the effects of sample size on effect size are discussed. (Contains 1 table and 4 figures.)
| Original language | English |
|---|---|
| Pages (from-to) | 500-506 |
| Number of pages | 7 |
| Journal | Educational Evaluation and Policy Analysis |
| Volume | 31 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Dec 2009 |
Bibliographical note
Database: ERICRecord type: New.
Language: English
DataStar source field: Educational Evaluation and Policy Analysis, 2009, vol. 31, no. 4, p. 500-506, pp. 7, 23 refs., ISSN: 0162-3737.
DataStar update date: 20100206
Keywords
- systematic reviews
- sample size
- effect size
- BEST-EVIDENCE SYNTHESIS
- METAANALYSIS
- PUBLICATION
- INSTRUCTION
- PROGRAMS
- QUALITY
- TRIALS
- ISSUES
- BIAS