Relative Accuracy of Pearson (3) and Log-Pearson (3) Distributions using three parameter estimation methods for modelling Hydrological Flood Data of Indus River at Sukkur Barrage

Abstract

In this study, Pearson (3) and Log-Pearson (3) distributions are fitted on the data of flood peaks at Sukkur barrage, using Method of Moment (MOM), Maximum Likelihood Method (MLM) and probability weighted Moments (PWM) for quantile estimation x²-test, S-K test, probability plot correlation Coefficient (PPCC), root mean square errors (RMSE), coefficient of skewness (Cs), Coefficient of Kurtosis (CK) and L - moment ratios are used for comparison and testing of the distribution and methods of etimation. LP (3) appears better than P (3) while MLM is more efficient than MOM. A flood of 1.233 million cusecs is expected to pass through Sukkur barrage during next 100 years by fitting LP (3), using MLM. Thus there is a need for taking suitable steps to save the structure of the barrage as its present capacity is only 0.9 million cusecs.