Measurement error (i.e. the complement of reliability) results in a downward bias of observed effect sizes. This attenuation can be reversed by disattenuation.

disattenuate.d(d, reliability)

Arguments

d

The (attenuated) value of Cohen's d (i.e. the value as observed in the sample, and therefore attenuated (decreased) by measurement error in the continuous variable).

reliability

The reliability of the measurements of the continuous variable

Value

The disattenuated value of Cohen's d

References

Bobko, P., Roth, P. L., & Bobko, C. (2001). Correcting the Effect Size of d for Range Restriction and Unreliability. Organizational Research Methods, 4(1), 46–61. doi:10.1177/109442810141003

Author

Gjalt-Jorn Peters & Stefan Gruijters

Examples

disattenuate.d(.5, .8);
#> [1] 0.559017