Abstract: Probability graph model is a general term for a class of graph patterns that express the probabilistic model,and the problem of solving the loss cost by using the model has become a hot research hotspot.In this paper,the three-way decision model was put forward based on probability graph and three-way decision theory.By analyzing the information data set,the Bayesian network of the model is constructed.Then according to the interdependencies of the nodes in the model,the conditional probability distribution function is calculated.And combining with the prior condition of the data set and three decision-making cost loss function,its decision rules are established.The method to solve the problem of cost minimization is given in probability reasoning decision-making.Finally,a teaching evaluation illustration was presented to verify the effectiveness of model.

Key words: Three-way decision,Probabilistic graph model,Bayesian network,Precise reasoning