Average prediction mean squared error.
An object of class
Hocking's Sp of the model.
Hocking's Sp criterion is an adjustment of the residual sum of Squares. Minimize this criterion. $$MSE / (n - p - 1)$$
where \(MSE = SSE / (n - p)\), n is the sample size and p is the number of predictors including the intercept
Hocking, R. R. (1976). The Analysis and Selection of Variables in a Linear Regression. Biometrics 32:150.
model <- lm(mpg ~ disp + hp + wt + qsec, data = mtcars) ols_hsp(model)#>  0.2644378