Simpson Dominance Index
index_simpson(x, ...)# S4 method for numeric
index_simpson(x, evenness = FALSE, unbiased = FALSE, na.rm = FALSE, ...)
A numeric vector.
N. Frerebeau
The Simpson index expresses the probability that two individuals randomly picked from a finite sample belong to two different types. It can be interpreted as the weighted mean of the proportional abundances. This metric is a true probability value, it ranges from \(0\) (all taxa are equally present) to \(1\) (one taxon dominates the community completely).
This is a dominance index, so that an increase in the value of the index accompanies a decrease in diversity.
Simpson, E. H. (1949). Measurement of Diversity. Nature, 163(4148), 688-688. tools:::Rd_expr_doi("10.1038/163688a0").
Other alpha diversity measures:
index_ace(),
index_baxter(),
index_berger(),
index_boone(),
index_brillouin(),
index_chao1(),
index_chao2(),
index_hurlbert(),
index_ice(),
index_margalef(),
index_mcintosh(),
index_menhinick(),
index_shannon(),
index_squares(),
observed()