Use Hill Number N2 when you need to convert a Simpson concentration to the Hill number of order two as its reciprocal. Enter Simpson concentration using the definitions and units below so the result can be reproduced.

Simpson concentration

A finite measured or assumed value.

The published tool contract uses this rule: Convert a Simpson concentration to the Hill number of order two as its reciprocal.

Hill number N2

The calculated hill number n2.

A ratio or percentage can conceal the scale of its numerator and denominator and becomes sensitive to measurement error when the denominator is small.

Retain the original Simpson concentration values and their units alongside the result. Hill Number N1 is useful when you instead need to convert a natural-log Shannon entropy to the Hill number of order one, the effective number of equally common species, as exp(H). Hill Number N0 provides another view by helping you return the Hill number of order zero, which equals species richness and therefore passes the species count through unchanged.

• Hill Number N1

  Convert a natural-log Shannon entropy to the Hill number of order one, the effective number of equally common species, as exp(H).

• Hill Number N0

  Return the Hill number of order zero, which equals species richness and therefore passes the species count through unchanged.

• Whittaker Beta Pairwise

  Compute pairwise Whittaker beta diversity between two sites as the mean site species richness divided by the number of shared species.