Mayuening Eso, Metta Kuning and Somporn Chuai-Aree

pp. 81 - 88

Abstract

The presented study aims to classify precipitation regions, analyze trends, and fit an appropriate model for daily
precipitation in Thailand. Factor analysis and generalized linear model (GLM) with gamma regression are performed on the
historical records of daily rainfall amounts from 114 weather stations during 2001 to 2012. The study shows that the factor
analysis divides the area of Thailand into seven regions with explanation of 58.9% of the total variance. The conducted gamma
models reveal a good fit for the upper part, south-east, and south-west of the examined regions. The deviance residual plots
from these models also provide a reasonable fit.

Keywords

• daily rainfall
• daily precipitation
• factor analysis
• gamma regression
• GLM