Conversion from Cohen's d to Common Language Effect Size
conversion.d.to.cles.Rd
Helper function to convert Cohen's d to common language effect size (or vice versa). The result is the probability of superiority for independent samples. It can be interpreted as the probability that a randomly selected observation from Group 1 exceeds a randomly selected observation from Group 2. The rationale is the same for paired-samples and one-sample designs, but the interpretation differs: For paired samples, it can be interpreted as the probability that the difference score (i.e., the score under Condition 1 minus the score under Condition 2) is greater than zero for a randomly selected individual. For a one-sample design, it can be interpreted as the probability that a randomly selected observation is greater than the reference value (e.g., 0).
Examples
d.to.cles(0.20) # small
#> cles d
#> 0.5562315 0.2000000
d.to.cles(0.50) # medium
#> cles d
#> 0.6381632 0.5000000
d.to.cles(0.80) # large
#> cles d
#> 0.7141962 0.8000000
cles.to.d(0.5562315)
#> d cles
#> 0.2000002 0.5562315
cles.to.d(0.6381632)
#> d cles
#> 0.5000000 0.6381632
cles.to.d(0.7141962)
#> d cles
#> 0.8000001 0.7141962