Internal function that fits a single GEV distribution to the model-averaged quantile curve, producing surrogate GEV parameters that approximate the model-averaged quantile function.
surrogate(zpf.surr = NULL, xqa, init.surr)A list (from optim()) with additional components:
Surrogate GEV parameters (mu, sigma, xi)
Quantiles from the surrogate model at xqa
The input model-averaged quantiles
Numeric vector of model-averaged quantiles at xqa.
Numeric vector of probabilities at which quantiles are evaluated.
Initial GEV parameter estimates for optimization.