Likelihood, score function and information matrix, bias, approximate ancillary statistics and sample space derivative for the generalized extreme value distribution
Arguments
- par
vector of
loc
,scale
andshape
- dat
sample vector
- method
string indicating whether to use the expected (
'exp'
) or the observed ('obs'
- the default) information matrix.- V
vector calculated by
gev.Vfun
- n
sample size
- p
vector of probabilities
Usage
gev.ll(par, dat)
gev.ll.optim(par, dat)
gev.score(par, dat)
gev.infomat(par, dat, method = c('obs','exp'))
gev.retlev(par, p)
gev.bias(par, n)
gev.Fscore(par, dat, method=c('obs','exp'))
gev.Vfun(par, dat)
gev.phi(par, dat, V)
gev.dphi(par, dat, V)
Functions
gev.ll
: log likelihoodgev.ll.optim
: negative log likelihood parametrized in terms of location,log(scale)
and shape in order to perform unconstrained optimizationgev.score
: score vectorgev.infomat
: observed or expected information matrixgev.retlev
: return level, corresponding to the \((1-p)\)th quantilegev.bias
: Cox-Snell first order biasgev.Fscore
: Firth's modified score equationgev.Vfun
: vector implementing conditioning on approximate ancillary statistics for the TEMgev.phi
: canonical parameter in the local exponential family approximationgev.dphi
: derivative matrix of the canonical parameter in the local exponential family approximation
References
Firth, D. (1993). Bias reduction of maximum likelihood estimates, Biometrika, 80(1), 27--38.
Coles, S. (2001). An Introduction to Statistical Modeling of Extreme Values, Springer, 209 p.
Cox, D. R. and E. J. Snell (1968). A general definition of residuals, Journal of the Royal Statistical Society: Series B (Methodological), 30, 248--275.
Cordeiro, G. M. and R. Klein (1994). Bias correction in ARMA models, Statistics and Probability Letters, 19(3), 169--176.