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Cliff’s delta (effect size)

Non-parametric effect size: (P(X>Y) − P(X<Y)). Based on all pairwise comparisons.

Inputs

Delta ranges from −1 to +1. Positive means Group 1 tends to be larger.

Result

Computed ✅
n1: 5 · n2: 5
#(x>y): 20 · #(x<y): 1 · #(x=y): 4
Cliff’s delta: 0.76
Magnitude: large
Interpretation: large effect (rule-of-thumb). Positive means group 1 tends to be larger.
Step-by-step
  1. Count pairwise dominance

    Formula: Compare all pairs (x in G1, y in G2)
    Substitute: Total pairs = 5·5 = 25
    Result: gt=20, lt=1, eq=4
  2. Compute Cliff’s delta

    Formula: δ = (gt − lt) / (n1·n2)
    Substitute: (20 − 1) / 25
    Result: δ = 0.76
  3. Magnitude (rule-of-thumb)

    Formula: |δ| thresholds: 0.147, 0.33, 0.474
    Substitute: |δ| = 0.76
    Result: large