6.1 Prediction model, gray model

The gray model is also a predictive model, which is quite fun. It is suitable for small-scale data with strong regularity but easy to be disturbed.

Generally, the data is drawn as a scatter plot or several data are summed to make a scatter plot to see the regularity. If there is an obvious fitting curve, it can be used.

Reference: http://blog.csdn.net/wyh7280/article/details/48230107

http://blog.sina.com.cn/s/blog_656fe31a0100hs3w.html

http://www.docin.com/p-1184148735.html

https://baike.baidu.com/item/%E7%81%B0%E8%89%B2%E9%A2%84%E6%B5%8B/7534704