Effect sizes
Cliff's delta
Implemented
effect-size.cliffs_deltaDefinition
Non-parametric effect size: the probability that a value from one group exceeds a value from the other, minus the reverse.
Formula
δ = (#(a_i > b_j) − #(a_i < b_j)) / (n_a · n_b)
Range: [−1, 1]
Inputs and outputs
- a: first sample
- b: second sample
Returns: result object
Assumptions
No assumptions beyond valid, aligned inputs of the documented types.
Limitations
No metric-specific limitations are documented yet. Interpret the value alongside the task, data, and other metrics.
Python API
import evalsuite as es
es.cliffs_delta(a, b)References
- Cliff N. Dominance statistics: ordinal analyses to answer ordinal questions. Psychol Bull. 1993;114(3):494-509.