Elementary mathematics method. Mainly used in some static, linear and deterministic models. Such as the allocation of seats, the comparison of students' grades, and some simple static models of infectious diseases.

Data analysis method. From a large number of observation data, a mathematical model is established by statistical methods such as regression analysis and time series analysis.

Simulation and other methods. There are mainly computer simulation (which is a statistical estimation method, equivalent to sampling inspection, and can be used for discrete system simulation and continuous system simulation), factor test method (which is mainly to do local experiments on the system and make continuous analysis and modification according to the test results to obtain the required model structure) and artificial reality method (based on the understanding of the system and the goals to be achieved).

Analytic hierarchy process. Mainly used in economic planning and management, energy decision-making and distribution, behavioral science, military science, military command, transportation, agriculture, education, talent, medical care, environment and other fields for decision-making, evaluation, analysis and prediction. The key step of this method is to establish a hierarchical structure model.