Interpret Standardized Differences — interpret_cohens

Interpretation of standardized differences using different sets of rules of thumb.

Usage

interpret_cohens_d(d, rules = "cohen1988", ...)

interpret_hedges_g(g, rules = "cohen1988")

interpret_glass_delta(delta, rules = "cohen1988")

Arguments

d, g, delta: Value or vector of effect size values.
rules: Can be "cohen1988" (default), "gignac2016", "sawilowsky2009", "lovakov2021" or a custom set of rules().
...: Not directly used.

Rules

Rules apply to equally to positive and negative d (i.e., they are given as absolute values).

Cohen (1988) ("cohen1988"; default)
- d < 0.2 - Very small
- 0.2 <= d < 0.5 - Small
- 0.5 <= d < 0.8 - Medium
- d >= 0.8 - Large
Sawilowsky (2009) ("sawilowsky2009")
- d < 0.1 - Tiny
- 0.1 <= d < 0.2 - Very small
- 0.2 <= d < 0.5 - Small
- 0.5 <= d < 0.8 - Medium
- 0.8 <= d < 1.2 - Large
- 1.2 <= d < 2 - Very large
- d >= 2 - Huge
Lovakov & Agadullina (2021) ("lovakov2021")
- d < 0.15 - Very small
- 0.15 <= d < 0.36 - Small
- 0.36 <= d < 0.65 - Medium
- d >= 0.65 - Large
Gignac & Szodorai (2016) ("gignac2016", based on the d_to_r() conversion, see interpret_r())
- d < 0.2 - Very small
- 0.2 <= d < 0.41 - Small
- 0.41 <= d < 0.63 - Moderate
- d >= 0.63 - Large

References

Lovakov, A., & Agadullina, E. R. (2021). Empirically Derived Guidelines for Effect Size Interpretation in Social Psychology. European Journal of Social Psychology.
Gignac, G. E., & Szodorai, E. T. (2016). Effect size guidelines for individual differences researchers. Personality and individual differences, 102, 74-78.
Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd Ed.). New York: Routledge.
Sawilowsky, S. S. (2009). New effect size rules of thumb.

Examples

interpret_cohens_d(.02)
#> [1] "very small"
#> (Rules: cohen1988)
#> 
interpret_cohens_d(c(.5, .02))
#> [1] "medium"     "very small"
#> (Rules: cohen1988)
#> 
interpret_cohens_d(.3, rules = "lovakov2021")
#> [1] "small"
#> (Rules: lovakov2021)
#>