The Pooled Standard Deviation is a weighted average of standard deviations for two or more groups, with more "weight" given to larger sample sizes.

sd_pooled(x, y = NULL, data = NULL)

mad_pooled(x, y = NULL, data = NULL)

Arguments

x

A formula, a numeric vector, or a name of one in data.

y

A numeric vector, a grouping (character / factor) vector, a or a name of one in data. Ignored if x is a formula.

data

An optional data frame containing the variables.

Value

Numeric, the pooled standard deviation.

Examples

sd_pooled(mpg ~ am, data = mtcars)
#> [1] 4.902029