灰色理论认为系统的行为现象尽管是朦胧的，数据是复杂的，但它毕竟是有序的，是有整体功能的。灰数的生成，就是从杂乱中寻找出规律。同时，灰色理论建立的是生成数据模型，不是原始数据模型，因此，灰色预测是一种对含有不确定因素的系统进行预测的方法。(The grey theory holds that although the behavior of the system is obscure and the data is complex, it is orderly and integral. The generation of grey numbers is to find the law from the clutter. At the same time, the grey theory is to build the data model, not the original data model, therefore, grey forecasting is a method to predict the system with uncertain factors.)