Access information from model objects

Description

Several functions to retrieve information from model objects, like variable names, link-inverse function, model frame etc.

Usage

pred_vars(x)

resp_var(x)

resp_val(x)

link_inverse(x)

model_frame(x, fe.only = TRUE)

var_names(x)

Arguments

Value

For pred_vars() and resp_var(), the name(s) of the response or predictor variables from x as character vector. resp_val() returns the values from x's response vector. link_inverse() returns, if known, the inverse link function from x; else NULL for those models where the inverse link function can't be identified. model_frame() is similar to model.frame(), but should also work for model objects that don't have a S3-generic for model.frame(). var_names() returns the "cleaned" variable names, i.e. things like s() for splines or log() are removed.

Examples

data(efc)
fit <- lm(neg_c_7 ~ e42dep + c161sex, data = efc)

pred_vars(fit)
resp_var(fit)
resp_val(fit)

link_inverse(fit)(2.3)

# example from ?stats::glm
counts <- c(18, 17, 15, 20, 10, 20, 25, 13, 12)
outcome <- gl(3, 1, 9)
treatment <- gl(3, 3)
m <- glm(counts ~ outcome + treatment, family = poisson())

link_inverse(m)(.3)
# same as
exp(.3)

outcome <- as.numeric(outcome)
m <- glm(counts ~ log(outcome) + as.factor(treatment), family = poisson())
var_names(m)