`Acc_rnd()` computes the expected accuracy of a random classifier based on the
class frequencies of the target. This measure can be used as a benchmark when contrasted
to the accuracy (in test) of a given prediction model.
Usage
Acc_rnd(target, freq = FALSE)
Arguments
- target
A character vector or a factor. Alternatively, a numeric vector
(see below).
- freq
TRUE if `target` contains the frequencies of the classes (in this
case, `target` should be numeric), FALSE otherwise. (Defaults: FALSE).
Value
Expected accuracy of a random classification model (a single value).
Examples
# Expected accuracy of a random model:
target <- c(rep("a",5),rep("b",2))
Acc_rnd(target)
#> [1] 0.5918367
# This is the same than:
freqs <- c(5/7,2/7)
Acc_rnd(freqs,freq=TRUE)
#> [1] 0.5918367
