Stein's weighted generalized Pareto likelihood
stein_gp_lik(pars, xdat, weights = rep(1, length(xdat)), ...)vector of length with scale and shape parameters
vector of exceedances in decreasing order if sort=FALSE
vector of weights
additional arguments, currently ignored
Stein, M.L. (2023). A weighted composite log-likelihood approach to parametric estimation of the extreme quantiles of a distribution. Extremes 26, 469-507 <doi:10.1007/s10687-023-00466-w>