Diversity Index Calculator

Diversity Index Formulas:

\[ \text{Simpson} = 1 - \sum_{i=1}^{R} p_i^2 \] \[ \text{Shannon} = -\sum_{i=1}^{R} p_i \ln(p_i) \]

Diversity Index Result:

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1. What Is Diversity Index?

Diversity indices are quantitative measures that reflect how many different types (such as species) there are in a dataset, while simultaneously taking into account how evenly the basic entities (such as individuals) are distributed among those types.

2. How Diversity Indices Are Calculated

The calculator provides two common diversity indices:

\[ \text{Simpson Index} = 1 - \sum_{i=1}^{R} p_i^2 \] \[ \text{Shannon Index} = -\sum_{i=1}^{R} p_i \ln(p_i) \]

Where:

\( p_i \) — Proportion of individuals belonging to the i-th species
\( R \) — Total number of species
\( \ln \) — Natural logarithm

Explanation: Simpson index gives more weight to common species, while Shannon index gives more weight to rare species.

3. Importance Of Diversity Measurement

Details: Diversity indices are crucial in ecology for assessing ecosystem health, in business for measuring market competition, and in information science for analyzing data complexity.

4. Using The Calculator

Tips: Enter counts of individuals for each species/type separated by commas (e.g., "5,10,15"). Select the index type you want to calculate.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between Simpson and Shannon indices?
A: Simpson index (range 0-1) emphasizes dominant species, while Shannon index (typically 1.5-3.5) is more sensitive to species richness.

Q2: What do the values mean?
A: Higher values indicate greater diversity. Simpson near 1 or Shannon >3 indicates high diversity.

Q3: When should I use which index?
A: Use Simpson when dominant species are important; Shannon when rare species matter more.

Q4: Are there limitations to these indices?
A: They don't account for species identity or ecological function, just abundance distribution.

Q5: Can I use this for non-ecological data?
A: Yes! These indices work for any categorical data where you can count occurrences.