Deviance of a Fitted Model - Generic Function

DESCRIPTION:
Returns the deviance or weighted residual sum of squares of the model.

This function is generic (see Methods); method functions can be written to handle specific classes of data. Classes which already have methods for this function include: gam, glm, lm, tree.


USAGE:
deviance(object, ...)

REQUIRED ARGUMENTS:
object:
a fitted model object.

OPTIONAL ARGUMENTS:
...:
methods may have additional arguments.

VALUE:
the deviance of the fitted model is returned.

DETAILS:
For glm, gam, and tree models, the "deviance" is a component of object, in which case deviance is a simple extractor function. For other models, the gaussian family is assumed and the weighted residual sum of squares is returned.