2.1. Projection Pursuit Grade Evaluation Model (PPE)
PP was established in 1969 by American scientists Kruskal, which was a valuable new and high technology, used for high-dimensional observation data analysis and processing, was an interdisciplinary field of computer science and technology, statistical theory and applied mathematics, belongs to the frontier today (Q Fu & Zhao, 2006). Through the transformation of higher dimensional data to lower dimensional space, looking for a projection value that can reflect the structure and characteristics of high-dimensional data, so research and analysis the higher dimensional data. It had a lot of advantages, such as strong anti-interference, good robustness, high accuracy, and so on. at present, had been widely applied in prediction (Hassanzadeh, Ebrahimi, Kompany-Zareh, & Ghavami, 2016), classification(Liu, Zhao, Liang, & Wu, 2014), quantitatively evaluate(F. Fang et al., 2016; Pei, Fu, Liu, Li, & Cheng, 2016),and many other areas, a group of gratifying achievements.