predict.lmRob: Use predict() on an lmRob Object

Description

Extracts the fitted values from an lmRob object and returns a matrix of predictions.

Usage

# S3 method for lmRob
predict(object, newdata, type = "response", se.fit = FALSE, terms = labels(object), ...)

Value

a vector of predictions, or a list consisting of the predictions and their standard errors if se.fit = TRUE.

Arguments

object: an lmRob object.
newdata: a data frame containing the values at which predictions are required. This argument can be missing, in which case predictions are made at the same values used to compute the object. Only those predictors referred to in the right side of the formula in object need be present by name in newdata.
type: a single character value specifying the type of prediction. The only choice is "response". If "response" is selected, the predictions are on the scale of the response.
se.fit: a logical value. If TRUE, pointwise standard errors are computed along with the predictions.
terms: this argument is presently unused.
...: additional arguments required by the generic predict function.

Warning

predict can produce incorrect predictions when the newdata argument is used if the formula in object involves data-dependent transformations, such as poly(Age, 3) or sqrt(Age - min(Age)).

Examples

Run this code

data(stack.dat)
stack.rob <- lmRob(Loss ~ ., data = stack.dat)
predict(stack.rob)
predict(stack.rob, newdata = stack.dat[c(1,2,4,21), ], se.fit = TRUE)