The first problem is the evaluation problem, which needs to collect data to calculate the dependent variable (that is, the score of ecological environment) and the independent variable (such as oxygen, water source, etc.). ). Since the restoration of Saihanba is a time dimension change, we need to collect variable data before and after the restoration of Saihanba.

Realizable models: rank sum ratio evaluation method, principal component analysis (there are too many independent variables, so the dimension can be reduced)