Attenuate a Cohen's d estimate for unreliability in the continuous variable

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

attenuate.d(d, reliability)

Arguments

d

The value of Cohen's d (that would be obtained with perfect measurements)

reliability

The reliability of the measurements of the continuous variable

Value

The attenuated 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

attenuate.d(.5, .8);
#> [1] 0.4472136