Use Selection Intensity i when you need to compute the standardized selection intensity as the signed selection difference divided by the phenotypic standard deviation. Enter Selection difference S and Phenotypic SD using the definitions and units below so the result can be reproduced.

Selection difference S

A finite measured or assumed value.

Phenotypic SD

Phenotypic standard deviation of the trait.

The published tool contract uses this rule: Compute the standardized selection intensity as the signed selection difference divided by the phenotypic standard deviation.

Selection intensity i

The calculated selection intensity i.

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 Selection difference S and Phenotypic SD values and their units alongside the result. Response To Selection is useful when you instead need to compute the breeder's equation response to selection as heritability times the signed selection differential. Selection Differential provides another view by helping you compute the signed selection differential as the mean of selected parents minus the population mean.

• Response To Selection

  Compute the breeder's equation response to selection as heritability times the signed selection differential.

• Selection Differential

  Compute the signed selection differential as the mean of selected parents minus the population mean.

• Selection Coefficient

  Compute the selection coefficient s = 1 - w from a relative fitness w between 0 and 1.