Abstract: Based on the grey system theory and maximum entropy principle, the grey incidence decisionmaking with incomplete information is discussed by using analytical technique.A incidence degree coefficient formula for interval grey numbers is constructed, which extends classical grey incidence decision-making to the case of interval grey numbers.The case of project objective value with nullity is then discussed and the theory and method are given to fulfill the null values.Based on the satisfactory degree, an algorithm is established for grey interval incidence decision-making.This algorithm makes the decision-makig method more flexible and the result more practical.An example is used to demonstrate the rationality, practicability and validity of the algorithm.

Key words: entropy, null value, decision-making, grey system, interval grey number, grey incidence degree