Machine learning (ML) is a scientific study of algorithms and statistical models used in computer systems, aiming at effectively performing specific tasks without explicit instructions. It is regarded as a subset of artificial intelligence. Machine learning algorithm constructs a mathematical model based on sample data, which is called "training data", so as to make predictions or decisions without explicit programming to perform tasks. [1][2] Machine learning algorithms are used in various applications, such as email filtering and computer vision, in which it is not feasible to develop algorithms for specific instructions to perform tasks. Machine learning is closely related to computational statistics, which focuses on using computers to make predictions. The research of algorithm optimization provides methods, theories and application fields for machine learning. Data mining is a research field of machine learning, focusing on exploratory data analysis to unsupervised learning. [3][4] In the application of cross-business problems, machine learning is also called predictive analysis.