Index Of Diversity Formula

Simpson's Diversity Index:

\[ ID = 1 - \sum (p_i)^2 \]

Simpson's Diversity Index (ID):

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1. What is Simpson's Diversity Index?

Simpson's Diversity Index is a measure of biodiversity that quantifies the probability that two individuals randomly selected from a sample will belong to the same species. It ranges from 0 (no diversity) to 1 (infinite diversity).

2. How Does the Calculator Work?

The calculator uses Simpson's Diversity Index formula:

\[ ID = 1 - \sum (p_i)^2 \]

Where:

\( ID \) — Simpson's Diversity Index (dimensionless)
\( p_i \) — Proportion of species i in the community
\( \sum \) — Summation over all species

Explanation: The index measures diversity by considering both species richness (number of species) and species evenness (distribution of individuals among species).

3. Importance of Diversity Index

Details: Simpson's Diversity Index is widely used in ecology, conservation biology, and environmental science to assess ecosystem health, monitor biodiversity changes, and compare different habitats.

4. Using the Calculator

Tips: Enter the number of species first, then input the proportion of each species (values between 0 and 1). The sum of all proportions must equal 1.

5. Frequently Asked Questions (FAQ)

Q1: What does a high diversity index value mean?
A: Higher values indicate greater biodiversity. Values closer to 1 suggest many species with relatively equal abundances.

Q2: How does Simpson's Index differ from Shannon Index?
A: Simpson's Index is more sensitive to dominant species, while Shannon Index is more sensitive to rare species. Both provide complementary information.

Q3: What is the range of Simpson's Diversity Index?
A: The index ranges from 0 to 1, where 0 indicates no diversity (all individuals belong to one species) and 1 indicates infinite diversity.

Q4: When should I use Simpson's Index?
A: Use it when you want to emphasize the probability of interspecific encounters or when dominant species are of particular interest.

Q5: How should proportions be calculated?
A: Proportions are calculated as the number of individuals of a species divided by the total number of individuals in the sample.