摘要
目的:探索黄瓜霜霉病发病趋势自回归模型。方法:借鉴传染病常微分SIR模型理论,构造含二次项的黄瓜霜霉病发病趋势自回归曲线模型;用一组黄瓜霜霉病时间序列模拟自回归模型参数,再用另一组黄瓜霜霉病序列进行验证。结果:黄瓜霜霉病一阶自回归模型为I(t+1)=0.0061I(t)(100-I(t))+0.9965I(t)+0.9084,模型的拟合优度检验为:残差平方和为133.1687,决定系数为0.9897,根均方误差为4.0800。一阶自回归模型拟合优度高于二阶自回归模型。结论:模型拟合效果较理想,可以利用该模型对只有发病状况的黄瓜霜霉病时间序列进行预测。
Objective:To explore an autoregressive model of forecasting the cucumber downy mildew disease morbidity(CDMDM). Methods: Based on the theory of infective ordinary differential equation (SIR model), we constructed an autoregressive curvilinear model of CDMDM containing a square term. The parameters of the model were simulated by a time series of cucumber downy mildew disease, and another time series of cucumber downy mildew disease was used to validate the model. Results: The first-order autoregressive model of CDMD was obtained as I (t+1)= 0.006 1 I (t)(100-I (t))+ 0.996 5I (t)+ 0.908 4. Fitting goodness test showed that sum of squared errors was 133.168 7, the coefficient of determination was 0.989 7, and the root mean squared error was 4.080 0. The first-order autoregressive model was better than the second-order model. Conclusion: The model has satisfactory fitting goodness and can be employed to forecast the trend of CDMDM.
出处
《第二军医大学学报》
CAS
CSCD
北大核心
2005年第6期684-686,共3页
Academic Journal of Second Military Medical University
基金
上海市科委科技攻关计划(03DZ19314).
