mev (version 1.17)

ibvpot: Interpret bivariate threshold exceedance models

Description

This is an adaptation of the evir package interpret.gpdbiv function. interpret.fbvpot deals with the output of a call to fbvpot from the evd and to handle families other than the logistic distribution. The likelihood derivation comes from expression 2.10 in Smith et al. (1997).

Usage

ibvpot(fitted, q, silent = FALSE)

Value

an invisible numeric vector containing marginal, joint and conditional exceedance probabilities.

Arguments

fitted

the output of fbvpot or a list. See Details.

q

a vector of quantiles to consider, on the data scale. Must be greater than the thresholds.

silent

boolean; whether to print the interpretation of the result. Default to FALSE.

Author

Leo Belzile, adapting original S code by Alexander McNeil

Details

The list fitted must contain

• model a string; see bvevd from package evd for options

• param a named vector containing the parameters of the model, as well as parameters scale1, shape1,scale2 and shape2, corresponding to marginal GPD parameters.

• threshold a vector of length 2 containing the two thresholds.

• pat the proportion of observations above the corresponding threshold

References

Smith, Tawn and Coles (1997), Markov chain models for threshold exceedances. Biometrika, 84(2), 249--268.

See Also

interpret.gpdbiv in package evir

Examples

if (requireNamespace("evd", quietly = TRUE)) {
y <- rgp(1000,1,1,1)
x <- y*rmevspec(n=1000,d=2,sigma=cbind(c(0,0.5),c(0.5,0)), model='hr')
mod <- evd::fbvpot(x, threshold = c(1,1), model = 'hr', likelihood ='censored')
ibvpot(mod, c(20,20))
}