Compute rounding bias — rounding

Rounding often leads to bias, such that the mean of a rounded distribution is different from the mean of the original distribution. Call rounding_bias() to compute the amount of this bias.

Usage

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

Arguments

x: Numeric or string coercible to numeric.
digits: Integer. Number of decimal digits to which x will be rounded.
rounding: String. Rounding procedure that will be applied to x. See vignette("rounding-options"). Default is "up".
threshold, symmetric: Further arguments passed down to reround().
mean: Logical. If TRUE (the default), the mean total of bias will be returned. Set mean to FALSE to get a vector of individual biases the length of x.

Value

Numeric. By default of mean, the length is 1; otherwise, it is the same length as x.

Details

Bias is calculated by subtracting the original vector, x, from a vector rounded in the specified way.

The function passes all arguments except for mean down to reround(). Other than there, however, rounding is "up" by default, and it can't be set to "up_or_down", "up_from_or_down_from", or"ceiling_or_floor".

Examples

# Define example vector:
vec <- seq(from = 0.01, to = 0.1, by = 0.01)
vec
#>  [1] 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10

# The default rounds `x` up from 5:
rounding_bias(x = vec, digits = 1)
#> [1] 0.005

# Other rounding procedures are supported,
# such as rounding down from 5...
rounding_bias(x = vec, digits = 1, rounding = "down")
#> [1] -0.005

# ...or rounding to even with `base::round()`:
rounding_bias(x = vec, digits = 1, rounding = "even")
#> [1] -0.005