varFunc function

Variance Function Structure

If object is a one-sided formula, it is used as the argument to varFixed and the resulting object is returned. Else, if object already inherits from class "varFunc", such as all standard varClasses , it is returned unchanged.

varFunc(object)

Arguments

• object: either an one-sided formula specifying a variance covariate, or an object inheriting from class "varFunc", representing a variance function structure.

Returns

an object from class "varFunc", representing a variance function structure.

Author(s)

José Pinheiro and Douglas Bates bates@stat.wisc.edu

See Also

summary.varFunc, varFixed, varWeights.varFunc, coef.varFunc

Examples

vf1 <- varFunc(~age)