This function computes the robust Final Prediction Errors (RFPE) for a robust regression fit using M-estimates.
It is used internally by step.lmrobdetMM and not meant to be used
directly.
lmrobdetMM.RFPE(object, scale = NULL)the MM element (of class lmrob) in an object of class lmrobdetMM.
a numeric value specifying the scale estimate used to compute the RFPE. Usually this
should be the scale estimate from an encompassing model. If NULL, the scale estimate in
object is used.
the robust final prediction error (numeric).