Stochastic modeling of rainfall in peninsular Malaysia using Bartlett Lewis rectangular pulses models
Stochastic modeling of rainfall in peninsular Malaysia using Bartlett Lewis rectangular pulses models
复制标题
使用 Bartlett Lewis 矩形脉冲模型对马来西亚半岛降雨量进行随机建模
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
A. Jemain
中科院分区：
文献类型：
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作者：
I. Hanaish;K. Ibrahim;A. Jemain
本文研究了Bartlett刘易斯矩形脉冲降雨模式的三个版本，即原始Bartlett刘易斯模式（OBL）、修正Bartlett刘易斯模式（MBL）和2N单元型Bartlett刘易斯模式（BL 2n）。这些模型拟合的每小时降雨量数据从1970年至2008年从八打灵再也雨量站，位于马来西亚半岛。采用广义矩量法估计模型参数。在这种方法下，最小化两个不同的目标函数，其中涉及不同的权重函数，一个权重是成反比的方差和另一个是成反比的均方，进行使用Nelder-Mead优化技术。为了比较三种不同模式的性能，使用7月和11月的结果进行说明。这种性能是根据模型的拟合优度进行评估的。此外，还研究了参数估计对目标函数选择的敏感性。结果表明，BL 2n模型的性能略优于OBL模型，但最优模型是Modified Bartlett刘易斯MBL模型，特别是当目标函数中权重与方差成反比时。
Three versions of Bartlett Lewis rectangular pulse rainfall models, namely, the Original Bartlett Lewis (OBL), Modified Bartlett Lewis (MBL), and 2N-cell-type Bartlett Lewis model (BL2n), are considered. These models are fitted to the hourly rainfall data from 1970 to 2008 obtained from Petaling Jaya rain gauge station, located in Peninsular Malaysia. The generalized method of moments is used to estimate the model parameters. Under this method, minimization of two different objective functions which involve different weight functions, one weight is inversely proportional to the variance and another one is inversely proportional to the mean squared, is carried out using Nelder-Mead optimization technique. For the purpose of comparison of the performance of the three different models, the results found for the months of July and November are used for illustration. This performance is assessed based on the goodness of fit of themodels. In addition, the sensitivity of the parameter estimates to the choice of the objective function is also investigated. It is found that BL2n slightly outperforms OBL. However, the best model is theModified Bartlett Lewis MBL, particularly when the objective function considered involves weight which is inversely proportional to the variance.