知识与财富的链接
为了提高对东海县需水量的预测精度,将比重较大且表现出很高随机性的灌溉需水量从需水总量中单独划出,采用定额法按不同频率年型对其进行预测;以灰色预测模型和三次指数平滑模型的组合预测法对非灌溉需水量进行预测,在确定单个模型的权重时更多地考虑了近期残差对预测值的影响;将灌溉需水量和非灌溉需水量汇总即可得到最终的预测值.该方法对数据要求不高并且能够按照不同的概率给出相应的需水量范围,从东海县需水量的历史数据可以判断最终的预测成果比较合理.
In order to enhance the prediction accuracy of water demand in Donghai County, this paper extracted irrigation water demand quantity which counted high proportion and showed strong randomness from the total water demand. Quota analysis method was taken to predict irrigation water demand quantity on the basis of different frequency years. Compound prediction method composed with the smooth model SM2and the grey prediction model was taken to predict non-irrigation water demand. When the weight of each single model was set, the impacts in residual errors in recent periods on the prediction value were more considered. Final prediction could be available by summating the quantity of irrigation and non-irrigation water demand. This method requires less data and can give ranges of water demand quantity based on different probabilities. The final prediction result was reasonable judged by the history data of water demand in Donghai County.
