TY - JOUR T1 - Application of L-moment Theory in Flood Frequency Analysis of Central Catchments of Iran TT - کاربرد تئوری گشتاورهای خطی در تحلیل تناوب سیل حوزه‌های آبخیز مرکزی ایران JF - JCPP JO - JCPP VL - 7 IS - 1 UR - http://jcpp.iut.ac.ir/article-1-380-en.html Y1 - 2003 SP - 1 EP - 17 KW - L-moment KW - Probability weighted moments KW - Regional flood analysis. N2 - Numerous methods are used in the investigation of floods in catchments such as regional flood frequency analysis. Regional flood frequency analysis relies on physical, climatic and ecological characteristics of catchments and applies statistical methods to study flow records. Hosking and Wallis developed Probability Weighted Moments and presented L-moments statistics as a new tool for flood frequency analysis. In this paper, the theory of L-moments was used to study the flood frequency of central catchments of Iran. A number of 27 sites each with more than 5 years of observed data were studied. In the first step, the diagram of L-kurtosis versus L-skewness was used and proper distributions for each site were applied. In order to eliminate the heterogeneous sites, homogeneous tests based on D, H1, H2 and H3 criteria were performed indicating that two sites appeared to be heterogenous. Next, using Goodness of Fit Test, the best regional distributions were determined which are GL, GEV, GN, PE3 and GPA, respectively. Finally, quantile estimates for distributions accepted at a 90% level were presented. M3 ER -