object
an object inheriting from class gls, representing
a generalized least squares fitted linear model, or from class
gnls, representing a generalized nonlinear least squares
fitted linear model.
type
an optional character string specifying the type of
residuals to be used. If "response", the "raw" residuals
(observed - fitted) are used; else, if "pearson", the
standardized residuals (raw residuals divided by the c