Effect sizes
Cohen's d
Implemented
effect-size.cohens_dDefinition
Standardised mean difference using the pooled standard deviation.
Formula
d = (x̄₁ − x̄₂) / s_pooled
Inputs and outputs
- sample a
- sample b
Returns: EffectSizeResult
Assumptions
No assumptions beyond valid, aligned inputs of the documented types.
Limitations
- Conventional small/medium/large thresholds are context-free rules of thumb.
Python API
import evalsuite as es
es.cohens_d(scores_a, scores_b, paired=True)References
- Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd ed.). Lawrence Erlbaum Associates.