is.empty.model             package:stats             R Documentation

Check if a Model is Empty

Description:

     R model notation allows models with no intercept and no
     predictors. These require special handling internally. 
     'is.empty.model()' checks whether an object describes an empty
     model.

Usage:

     is.empty.model(x)

Arguments:

       x: A 'terms' object or an object with a 'terms' method.

Value:

     'TRUE' if the model is empty

See Also:

     'lm','glm'

Examples:

     y <- rnorm(20)
     is.empty.model(y ~ 0)
     is.empty.model(y ~ -1)
     is.empty.model(lm(y ~ 0))

