an object of class "formula" (Or one that can be coerced to that class): a symbolic description Of the model To be fitted. The details Of model specification are given under 'Details’. [as FormulaExpression]

a description of the error distribution and link function to be used in the model. For glm this can be a character string naming a family function, a family function or the result of a call to a family function. For glm.fit only the third option is supported. (See family for details of family functions.)

an optional data frame, list or environment (or object coercible by as.data.frame to a data frame) containing the variables in the model. If not found in data, the variables are taken from environment(formula), typically the environment from which glm is called.

[as Environment]