Research of default rules mining model based on reduced lattice

In order to solve the decision question with incomplete information and uncertainty of risk factors during the risk decision, the concept of reduced lattice is introduced into project risk management in this paper, then the default rule mining model based on the combination of rough set and reduced lattice is constructed, and created a series of subsystems from the known decision system at different reduced levels, then form a reduced lattice, and then deduce its own rule set at each reduced lattice. At last, an example is introduced to demonstrate the method and model above detailed.