基于Archimedean Copula的三维干旱特征变量联合分布研究

应用Archimedean Copula函数研究干旱特征变量的联合分布，为水资源决策者提供依据。以渭河流域西安站77年的月降水资料为例, 采用Archimedean Copulas函数建立干旱特征变量之间的三维联合分布模型。分别采用极大似然法和适线法进行参数估计，通过拟合优度评价选用Clayton Copula描述干旱历时，干旱烈度和干旱烈度峰值之间的联合分布，并计算条件重现期。结果表明, Copulas函数能够比较好的描述干旱特征变量间的联合分布；具有灵活性和应用范围广等特点。

Research on Three-dimensional Joint Distribution of Drought Characteristics Based on Archimedean Copulas

Applying copula function to the joint distribution of drought variables serves as a basis for water resources decision-makers.Taking 77 years of monthly precipitation data of Xi'an Gauge Station located in the Weihe River Basin as an example,this paper uses Archimedean Copula functions to establish the three-dimensional joint distributed model among drought variables.Maximum Likehood Estimation Method and Curve Fitting Method are used to estimate the parameters of copulas,then goodness of fit statistics is ...