Category Diversity Summary
Describe categorical distributions with Shannon entropy and effective category counts.
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Calculation results
Total: 40; observed categories: 3 of 4 supplied.
Shannon entropy: 1.03972 nats; effective Shannon categories: 2.82843.
Concentration Σp²: 0.375; effective Simpson categories: 2.66667.
Assumptions and limits
Shannon entropy is −sum(p log p), using natural logarithms (nats) and zero contribution for zero counts. Its exponential and inverse sum(p²) are effective category counts. These are descriptive plug-in summaries of mutually exclusive categories, not bias-corrected population richness estimates or uncertainty intervals. Zero-count categories affect the supplied category count but not entropy. Category definitions matter; do not interpret diversity alone as quality, equity or clinical benefit. Use 2–200 nonnegative integer counts, total 1–100 million.
SciPy entropy definition · Read the practical guide · Download blank worksheet (TXT)