Performance of L-moments and nonparametric flood frequency analysis

Abstract

A simulation study was undertaken to compare parametric L-moments and nonparametric approaches in flood frequency analysis. Data of various sample lengths were generated from a given generalized extreme value distribution and the quantiles estimated using the fixed-kernel nonparametric method and from a generalized extreme value distribution fitted by L-moments. From the resulting root-mean-square errors for various quantiles, it was concluded for unimodal distributions that nonparametric methods are preferable for large return period floods estimated from short (<30 years) samples while parametric methods are preferable in other circumstances. It was also pointed out that nonparametric methods are more suitable for mixed distributions. Key words: frequency analysis, L-moments, nonparametric methods, simulation.

Drought analysis of the Seyhan Basin by using standardized precipitation ındex (spı) and l-moments

“…One can infer roughly from Table 4 that drought have experienced quinquennial overall basin. (1970-1975-2005) Çamardı (1989-1992) Feke (1970-1975), (1984-1987), (1989-1991) Karaisalı (1970-1975), (1989), (2003-2009) Karataş (1982-1985, (1989)(1990)(1991)(1992), (2003)(2004)(2005)(2006)(2007) Pınarbaşı (1984-1987), (1989-1990-1994) Pozantı 1973, 1982, 1984, (1989) Sarız (1981-1985, (1999)(2000)(2001)(2002)(2003) Tomarza (1973( -1974( -2001( ) Tufanbeyli 1989( , 2001( , (2003( -2008 Ulukışla (1973-1975), (1981-1985), …”

“…Eslamian et al (2012) used two indexes of cumulative precipitation deficit (CPD) and maximum precipitation deficit (MPD) for evaluating the severity of drought in a certain month and regional frequency analysis has been carried out by L-moments. Gingras & Adamowski (1994) conduct a simulation study to compare parametric L-moments and nonparametric approaches in flood frequency analysis. Saf (2009) carried out a study to determine regional probability distributions for the annual maximum flood data observed at 45 streamflow gauging sites in the Kucuk and Buyuk Menderes River Basins in Turkey using index flood L moments.…”

Site-focused nonparametric test of regional homogeneity based on flood regime

“…Too large an h value will lead to a unimodal density regardless of the modality of the data, while too small an h will lead to a distorted multimodal density shape regardless of the modality of the data (Gingras and Adamowski, 1994). The smoothing factor h is estimated from the observed data based on a cross-validation technique that minimizes the integrated mean-square error (IMSE) expressed according to Silverman (1986) as…”

Methods for design flood estimation in South Africa

“…summarise approaches available for estimat- (2000) summarise approaches available for estimatsummarise approaches available for estimating the parameters of a selected distribution as the Method of Moments (MM), Maximum Likelihood Procedure (MLP), Probability Weighted Moments (PWM), L-Moments (LM), Bayesian Inference and non-parametric methods. The use of L-moments to fit distributions has received extensive coverage in the literature (Guttman, 1992;Pilon and Adamowski, 1992;Guttman, 1993;Guttman et al, 1993;Lin and �ogel, 1993;�ogel and Fennessy, 1993;Wallis, 1993;Gingras and Adamowski, 1994;Zrinji and Burn, 1994;Hosking, 1995;Hosking and Wallis, 1995;Karim and Chowdhury, 1995;Hosking and Wallis, 1997). L-moments are reported to have less bias when compared to other techniques.…”