R/error.R

In mhahsler/recommenderlab: Lab for Developing and Testing Recommender Algorithms

MAE <- function(true, predicted, na.rm = TRUE) {
  if (length(true) != length(predicted))
    stop("length does not match!")
  mean(abs(true - predicted), na.rm = na.rm)
}

MSE <- function(true, predicted, na.rm = TRUE) {
  if (length(true) != length(predicted))
    stop("length does not match!")
  mean((true - predicted) ^ 2, na.rm = na.rm)
}

RMSE <- function(true, predicted, na.rm = TRUE) {
  if (length(true) != length(predicted))
    stop("length does not match!")
  mean((true - predicted) ^ 2, na.rm = na.rm) ^ .5
}

frobenius <- function(true, predicted, na.rm = TRUE) {
  if (is.null(dim(true)) ||
      is.null(dim(predicted)))
    stop("matrix needed!")
  if (any(dim(true) != dim(predicted)))
    stop("matrix dimensions do not match!")
  RMSE(true, predicted, na.rm = na.rm)
}