Comparison of Progressive Variable Ordering Methods with Fixed Ordering Heuristics for Binary Decision Diagrams

Binary decision diagram (BDD) is an efficient algorithm applied in many domains. When used in the area of system risk assessment, the BDD technology can improve both qualitative and quantitative analysis of system failures by solving large fault trees. However, the size of a BDD depends critically on the decision variable ordering. This paper compared the new progressive ordering method with existing fixed ordering heuristics. The simulation results show a superior performance when using the progressive ordering method.