Pooled percent relative standard deviation (%RSD) across groups

pooled_sd() expressed as a percentage of the grand mean of x, i.e. a batch-pooled %CV. The pooled SD weights each group by its degrees of freedom and the grand mean weights each value equally, so both are consistently weighted by group size. See pooled_sd() for how groups are pooled.

Usage

pooled_rsd(x, group, na.rm = FALSE, min_n = 2L)

Arguments

x

a numeric vector

group

a vector the same length as x giving the pooling group of each value (e.g. batch_id)

na.rm

logical, if TRUE then NA values in x are stripped before pooling

min_n

integer, the minimum number of non-missing values a group must have to contribute. Groups with fewer than min_n are dropped; a group is always dropped below two values, which have no within-group variance. The default is 2.

Value

a single numeric value. NA_real_ if the grand mean is zero or NA, x is not numeric, or no group has enough replicates.

Examples

pooled_rsd(c(5, 6, 4, 15, 16, 14), group = c(1, 1, 1, 2, 2, 2))
#> [1] 10