线性矩法与常规矩法对太湖流域降雨频率分析的比较研究

摘要

This paper investigated the differences between conventional moments (C-M) and L-moments (L-M),when being applied to estimate parameter and design rainfalls in the Taihu Lake Basin.It introduced to the theory of L-moments,and provided the advantages of L-moments over conventional moments by comparison.With data of the Taihu Lake Basin,the performance of these tests was taken via a series of Monte Carlo simulation experiments.The four stations with longer rainfall data series were chosen to estimate design rainfalls by fitting the P-Ⅲ distributions based on the conventional moments and L-moments,respectively.The results show that L-M-based tests are more reasonable on annual extreme precipitation estimation and have better performance in terms of unbiasedness and robustness on parameter estimation over the C-M.%介绍了线性矩法的基本理论,并与常规矩法进行了初步的比较与分析,说明了其理论上的优越性;以太湖流域的雨量资料为例,选取4个站点分别应用线性矩法和常规矩法估计其不同重现期下年极值降雨频率设计值;最后,利用Monte Carlo方法对太湖流域内96个站点数据进行模拟,比较线性矩法和常规矩法所估计的统计参数.结果表明:线性矩法估计的参数在精确性、不偏性及稳健性方面较常规矩法更优.