concstats_simpson: Gini-Simpson Index
In concstats: Market Structure, Concentration and Inequality Measures

concstats_simpson

R Documentation

Gini-Simpson Index

Description

Gini-Simpson Index

Usage

concstats_simpson(x, na.rm = TRUE)

Arguments

`x`	A non-negative numeric vector.
`na.rm`	A logical vector that indicates whether `NA` values should be excluded or not. Must be either `TRUE` or `FALSE`. The default is `TRUE`. If set to `FALSE` the computation yields `NA` if `NA` values are present.

Details

concstats_simpson is the Gini-Simpson index, also known as the Gini impurity (Gini's diversity index) in Machine Learning, Gibbs-Martin index or Blau index in sociology and management studies. This index ranges from (0, 1).

Value

A single numeric value in decimal form.

References

Simpson, E. H. (1949). "Measurement of Diversity", Nature, 163, 688.

Jost, L. (2006). "Entropy and Diversity". Oikos, 113(2), 363-375.

Examples

# a vector of market shares
x <- c(0.4, 0.2, 0.25, 0.1, 0.05)
concstats_simpson(x)
# a vector with NA values
x <- c(0.4, 0.2, 0.25, 0.1, 0.05, NA)
concstats_simpson(x, na.rm = FALSE)

concstats documentation built on March 31, 2023, 10:26 p.m.