This function flips the L-moments by a flip attribute within an L-moment object such as that returned by lmomsRCmark. The function will attempt to identify the L-moment object and lmorph as necessary, but this support is not guaranteed. The flipping process is used to support left-tail censoring using the right-tail censoring alogrithms of lmomco. The odd order (seq(3,n,by2)) \(\lambda_r\) and \(\tau_r\) are negated. The mean \(\hat\lambda_1\) is computed by subtracting the \(\lambda_1\) from the lmom argument from the flip M: \(\hat\lambda_1 = M - \lambda_1\) and the \(\tau_2\) is subsequently adjusted by the new mean. This function is written to provide a convenient method to re-transform or back flip the L-moments computed by lmomsRCmark. Detailed review of the example problem listed here is recommended.
fliplmoms(lmom, flip=NULL, checklmom=TRUE)An R
list is returned that matches the structure of the lmom argument (unless an lmorph was attempted). The structure is intended to match that coming from lmomsRCmark.
A L-moment object created by lmomsRCmark or other vectorize L-moment list.
lmomsRCmark provides the flip, but for other vectorized L-moment list support, the flip can be set by this argument.
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.
W.H. Asquith
Wang, Dongliang, Hutson, A.D., and Miecznikowski, J.C., 2010, L-moment estimation for parametric survival models given censored data: Statistical Methodology, v. 7, no. 6, pp. 655--667.
Helsel, D.R., 2005, Nondetects and data analysis---Statistics for censored environmental data: Hoboken, New Jersey, John Wiley, 250 p.
lmomsRCmark