麦长管蚜风险因子随机模拟研究

Stochastic Simulate Risk Factor of Sitobion avenae

采用随机模拟方法 ,对北京市麦长管蚜风险因子的等级序列模拟和概率计算进行了探讨。首先对多年来风险因子序列的数据进行分级 ,确定其分布型。然后根据其分布型和分布特征值 ,使用matlab软件编程计算 ,产生各序列值对应分布型的累积分布函数值 ,并采用分布型随机数发生方法产生随机模拟序列。通过对北京市195 6～ 2 0 0 1年温度、降水量和 1982～ 1999年麦长管蚜发生量、发生期的 6个等级序列的模拟 ,能够计算出各个等级的概率 ,并产生通过F检验的模拟序列。

For calculate risk factor probability in pest risk analysis, this paper adopted a method of stochastic simulation, approach calculation of grade serials simulation and probability of Sitobion avenae in Beijing. Firstly, risk factors were divided into grade serials. Secondly, confirming what is distribution function of the grade serial. Thirdly, cumulative distribution function value of the grade serials were calculated by matlab software according to distributing function and eigenvalue. Fourthly, Monte Carlo methods mathematics can generate the grade serials. This method can be used to calculate the grade serials of temperature, precipitation from 1956 to 2001 and the population, emergence period of Sitobion avenae from 1982 to 1999 in Beijing. Results of calculation passed F test.