This help topic is for R version 3.1.1. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/stats/html/is.empty.html
is.empty.model {stats}R Documentation

Test if a Model's Formula is Empty

Description

R's formula 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))

[Package stats version 3.1.1 ]