parray {lmomco} | R Documentation |
This function estimates the parameters of the Rayleigh distribution given
the L-moments of the data in an L-moment object such as that returned by
lmom.ub
. The relations between distribution parameters and L-moments
are
α = frac{2λ_2sqrt{π}}{sqrt{2} - 1}mbox{,}
and
xi = λ_1 - αsqrt{π/2}mbox{.}
parray(lmom, xi=NULL, checklmom=TRUE)
lmom |
A L-moment object created by lmom.ub
or pwm2lmom . |
xi |
The lower limit of the distribution. If xi is known then alternative algorithms are used. |
checklmom |
Should the lmom be checked for validity using the are.lmom.valid function. Normally this should be left as the default and it is very unlikely that the L-moments will not be viable (particularly in the tau_4 and tau_3 inequality). However, for some circumstances or large simulation exercises then one might want to bypass this check. |
An R list
is returned.
type |
The type of distribution: ray . |
para |
The parameters of the distribution. |
source |
The source of the parameters: “parray”. |
W.H. Asquith
Hosking, J.R.M., 1986, The theory of probability weighted moments: Research Report RC12210, IBM Research Division, Yorkton Heights, N.Y.
lmom.ub
, lmomray
,
cdfray
, quaray
lmr <- lmom.ub(rnorm(20)) parray(lmr)