Fitted model deviance

Returns the deviance of a fitted model object.

# S3 method for ssn_lm
deviance(object, ...)

# S3 method for ssn_glm
deviance(object, ...)

Arguments

object

A fitted model object from ssn_lm() or ssn_glm().

...

Other arguments. Not used (needed for generic consistency).

Value

The deviance.

Details

The deviance is twice the difference in log-likelihoods between the saturated (perfect-fit) model and the fitted model.

Examples

# Copy the mf04p .ssn data to a local directory and read it into R
# When modeling with your .ssn object, you will load it using the relevant
# path to the .ssn data on your machine
copy_lsn_to_temp()
temp_path <- paste0(tempdir(), "/MiddleFork04.ssn")
mf04p <- ssn_import(temp_path, overwrite = TRUE)

ssn_mod <- ssn_glm(
  formula = Summer_mn ~ ELEV_DEM,
  ssn.object = mf04p,
  family = "Gamma",
  tailup_type = "exponential",
  additive = "afvArea"
)
deviance(ssn_mod)
#> [1] 9.832514e-05