rFormula function

Model formula for Rchoice models

Two kind of variables are used in models with individual heterogenetiy: the typical variables that enter in the latent process and those variables that enter in the random parameter (Hierarchical Model). rFormula deal with this type of models using suitable methods to extract the elements of the model.

rFormula(object)

is.rFormula(object)

## S3 method for class 'rFormula'
model.frame(formula, data, ..., lhs = NULL, rhs = NULL)

## S3 method for class 'rFormula'
model.matrix(object, data, rhs = NULL, ...)

Arguments

• object: a formula form the rFormula function, for the model.matrix method, a rFormula object,
• formula: a rFormula object,
• data: a data.frame,
• ...: further arguments.
• lhs: see Formula,
• rhs: see Formula,