Simpson Diversity Index
Find the chance that two different sampled items belong to different categories.
Your numbers
Gini–Simpson diversity
Use consistent units. The result follows the assumptions you enter.
Scenario comparison
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Formula
D=1−Σnᵢ(nᵢ−1)/[N(N−1)]
Find the chance that two different sampled items belong to different categories.
Worked example
- Category integer counts
- 10, 10, 10
- Gini–Simpson diversity
- 0.689655172414
Scope and limitations
Use consistent units. The result follows the assumptions you enter.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: 0e3740732631 · Example checked: