Compute rounding bias — rounding

Rounding changes the mean of a distribution. rounding_bias() computes this bias as the mean of the rounded values minus the mean of the original ones, or, with mean = FALSE, the individual differences.

Usage

rounding_bias(
  x,
  digits,
  rounding = "up",
  threshold = 5,
  symmetric = FALSE,
  mean = TRUE
)

Arguments

x: Numeric, or a string coercible to numeric.
digits: Integer. Number of decimal places to round to.
rounding: String. The rounding method. Default is "up". See vignette("rounding-options").
threshold, symmetric: Passed on to reround().
mean: Logical. If TRUE (the default), return the mean bias; otherwise, the individual biases.

Value

Numeric. Length 1 by default, or the length of x with mean = FALSE.

Details

All arguments except mean are passed on to reround(). Unlike there, rounding defaults to "up" and cannot be a compound method ("up_or_down", "up_from_or_down_from", "ceiling_or_floor"), since those return two rounded values per input and have no single bias.

Examples

vec <- 0.01 |> seq(0.1, by = 0.01) |> round(2)
vec
#>  [1] 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10

rounding_bias(x = vec, digits = 1)
#> [1] 0.005
rounding_bias(x = vec, digits = 1, rounding = "down")
#> [1] -0.005
rounding_bias(x = vec, digits = 1, rounding = "even")
#> [1] -0.005