Calculate variance-covariance matrix for a fitted model object

Calculate variance-covariance matrix for a fitted model object.

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

# S3 method for ssn_glm
vcov(object, var_correct = TRUE, ...)

Arguments

object: A fitted model object from ssn_lm() or ssn_glm().
...: Other arguments. Not used (needed for generic consistency).
var_correct: A logical indicating whether to return the corrected variance-covariance matrix for models fit using ssn_glm() (when family is different from "Gaussian"). The default is TRUE.

Value

The variance-covariance matrix of coefficients obtained via coef(). Currently, only the variance-covariance matrix of the fixed effects is supported.

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_lm(
  formula = Summer_mn ~ ELEV_DEM,
  ssn.object = mf04p,
  tailup_type = "exponential",
  additive = "afvArea"
)
vcov(ssn_mod)
#>             (Intercept)      ELEV_DEM
#> (Intercept) 77.68860270 -3.855169e-02
#> ELEV_DEM    -0.03855169  1.915303e-05