Probability Distribution Fitting of Rainfall Patterns in Philippine Regions for Effective Risk Management

Abstract

This study aims to determine the best fit frequency distribution of rainfall patterns for event forecasting in order to address potential disasters. The monthly rainfall data were taken from the PAGASA which are analyzed using Chi-Square and K-S goodness-of-fit tests. Rainfall data for the past 26-30 years was used to determine the distribution pattern fitted into more than 60 Probability Distribution Functions (PDF). The best fitted PDF both in Kolmogorov-Smirnov and in Chi-square tests were used in statistical inferences. Findings showed that each site has specific theoretical probability distribution functions to infer rainfall events. Varying levels of rainfall events were measured using the CDF. Consequently, the statistical inferences found in this study are important for designing optimum flood control facilities. Moreover, it is also contributory for the effective management of irrigation system of the National Irrigation Administration for a more efficient water supply to the agricultural sector.