Estimate the variance-covariance matrix of the joint (VaR, ES) estimator by the sandwich formula: $$\lambda^{-1} \Sigma \lambda^{-1}$$ Several estimators are available for both matrices and the default options are selected to take into account possible misspecifications in the underlying data.
vcovA(
object,
sigma_est = "scl_sp",
sparsity = "nid",
misspec = TRUE,
bandwidth_estimator = "Hall-Sheather"
)
An esreg object
The estimator to be used for \(\Sigma\), see conditional_truncated_variance
ind - Variance over all negative residuals
scl_N - Scaling with the normal distribution
scl_sp - Scaling with the kernel density function
The estimator to be used for the sparsity in \(\Lambda\), see density_quantile_function
iid - Piecewise linear interpolation of the distribution
nid - Hendricks and Koenker sandwich
if TRUE, the estimator accounts for potential misspecification in the model
The bandwidth estimator to be used for the iid and nid sparsity estimator, see density_quantile_function
Bofinger
Chamberlain
Hall-Sheather