Enables a conversion between different indices of effect size, such as
standardized difference (Cohen's d), correlation r or (log) odds ratios.
Usage
d_to_r(d, ...)
r_to_d(r, ...)
oddsratio_to_d(OR, log = FALSE, ...)
logoddsratio_to_d(OR, log = TRUE, ...)
d_to_oddsratio(d, log = FALSE, ...)
oddsratio_to_r(OR, log = FALSE, ...)
logoddsratio_to_r(OR, log = TRUE, ...)
r_to_oddsratio(r, log = FALSE, ...)
Value
Converted index.
Arguments
d
Standardized difference value (Cohen's d).
...
Arguments passed to or from other methods.
r
Correlation coefficient r.
OR
Odds ratio values in vector or data frame.
log
Take in or output the log of the ratio (such as in logistic models).
Details
Conversions between d and OR is done through these formulae:
\(d = \frac{\log(OR)\times\sqrt{3}}{\pi}\)
\(log(OR) = d * \frac{\pi}{\sqrt(3)}\)
Converting between d and r is done through these formulae:
\(d = \frac{2 * r}{\sqrt{1 - r^2}}\)
\(r = \frac{d}{\sqrt{d^2 + 4}}\)
The conversion from d to r assumes equally sized groups. The resulting
r is also called the binomial effect size display (BESD; Rosenthal et al.,
1982).
References
Sánchez-Meca, J., Marín-Martínez, F., & Chacón-Moscoso, S. (2003).
Effect-size indices for dichotomized outcomes in meta-analysis. Psychological
methods, 8(4), 448.
Borenstein, M., Hedges, L. V., Higgins, J. P. T., & Rothstein, H. R.
(2009). Converting among effect sizes. Introduction to meta-analysis, 45-49.
Rosenthal, R., & Rubin, D. B. (1982). A simple, general purpose display of
magnitude of experimental effect. Journal of educational psychology, 74(2), 166.
See Also
cohens_d()
Other convert between effect sizes:
diff_to_cles,
eta2_to_f2(),
odds_to_probs(),
oddsratio_to_riskratio()