Use FST Fixation Index when you need to compute the fixation index fst = (ht - hs) / ht for two populations at a two-allele locus. Enter Population X allele A frequency and Population Y allele A frequency using the definitions and units below so the result can be reproduced.

Population X allele A frequency

A finite measured or assumed value from 0 through 1.

Population Y allele A frequency

A finite measured or assumed value from 0 through 1.

The published tool contract uses this rule: Compute the fixation index fst = (ht - hs) / ht for two populations at a two-allele locus.^[1]

Fixation index FST

The calculated fixation index fst.

The calculation does not propagate measurement uncertainty, sampling error, or biological and chemical variability. Population X allele A frequency must remain between 0 and 1; Population Y allele A frequency must remain between 0 and 1.

Retain the original Population X allele A frequency and Population Y allele A frequency values and their units alongside the result. Brillouin Index is useful when you instead need to compute the Brillouin diversity index HB = (ln(N!) - sum(ln(ni!))) / N from three species counts using loop-based log factorials for communities up to 10000 individuals. Simpson Index D provides another view by helping you compute the Simpson diversity index D for three species counts in a sample.

• Brillouin Index

  Compute the Brillouin diversity index HB = (ln(N!) - sum(ln(ni!))) / N from three species counts using loop-based log factorials for communities up to 10000 individuals.

• Simpson Index D

  Compute the Simpson diversity index D for three species counts in a sample.

• Germination Rate Index

  Compute the germination rate index over two days as (day one count / 1 + day two count / 2) / seeds sown times 100, expressed in percent per day.