Monday, November 09, 2009

Effect size of matched and unmatched data in Maltab

"In statistics, an effect size is a measure of the strength of the relationship between two variables in a statistical population, or a sample-based estimate of that quantity" from here.

The script below calculates effect size for matched (paired) and unmatched (unpaired) data as described in [1].

So, if C and E sets are matched than effect size d is 1.265. If C and E sets are unmatched than effect size d is also 1.265. The two sizes are equal for this example only.

References

[1] Dunlop, W. P., Cortina, J. M., Vaslow, J. B., & Burke, M. J. (1996).
Meta-analysis of experiments with matched groups or repeated measures designs. Psychological Methods, 1, 170-177.