quawak {lmomco} | R Documentation |
This function computes the quantiles of the Wakeby distribution given
parameters (xi, α, β, gamma, and delta)
of the distribution computed by parwak
.
The quantile function of the distribution is
x(F) = xi+frac{α}{β}(1-(1-F)^β)- frac{gamma}{delta}(1-(1-F))^{-delta} mbox{,}
where x(F) is the quantile for nonexceedance probability F,
xi is a location parameter, α and β
are scale parameters, and gamma, and delta are
shape parameters. The five returned parameters from parwak
in order
are xi, α, β, gamma, and delta.
quawak(f, wakpara)
f |
Nonexceedance probability (0 <= F <= 1). |
wakpara |
The parameters from parwak or similar. |
Quantile value for nonexceedance probability F.
W.H. Asquith
Hosking, J.R.M., 1990, L-moments—Analysis and estimation of distributions using linear combinations of order statistics: Journal of the Royal Statistical Society, Series B, vol. 52, p. 105–124.
Hosking, J.R.M., 1996, FORTRAN routines for use with the method of L-moments: Version 3, IBM Research Report RC20525, T.J. Watson Research Center, Yorktown Heights, New York.
Hosking, J.R.M. and Wallis, J.R., 1997, Regional frequency analysis—An approach based on L-moments: Cambridge University Press.
lmr <- lmom.ub(c(123,34,4,654,37,78)) quawak(0.5,parwak(lmr))