predict.lqs               package:MASS               R Documentation

Predict from an lqs Fit

Description:

     Predict from an resistant regression fitted by 'lqs'.

Usage:

     ## S3 method for class 'lqs':
     predict(object, newdata, na.action = na.pass, ...)

Arguments:

  object: object inheriting from class '"lqs"' 

 newdata: matrix or data frame of cases to be predicted or, if 'object'
          has a formula, a data frame with columns of the same names as
          the variables used.  A vector will be interpreted as a row
          vector.  If 'newdata' is missing, an attempt will be made to
          retrieve the data used to fit the 'lqs' object. 

na.action: function determining what should be done with missing values
          in 'newdata'.  The default is to predict 'NA'.

     ...: arguments to be passed from or to other methods.

Details:

     This function is a method for the generic function 'predict()' for
     class 'lqs'. It can be invoked by calling 'predict(x)' for an
     object 'x' of the appropriate class, or directly by calling
     'predict.lqs(x)' regardless of the class of the object.

     Missing values in 'newdata' are handled by returning 'NA' if the
     linear fit cannot be evaluated. If 'newdata' is omitted and the
     'na.action' of the fit omitted cases, these will be omitted on the
     prediction.

Value:

     A vector of predictions.

Author(s):

     B.D. Ripley

See Also:

     'lqs'

Examples:

     data(stackloss)
     set.seed(123)
     fm <- lqs(stack.loss ~ ., data = stackloss, method = "S", nsamp = "exact")
     predict(fm, stackloss)

