Through experimental calculation, it can be obtained that the edge transfer probability of 70% of the data are greater 13 Urban Rail Transit (2023) 9:147–178 Fig. 6 Construction of a causal risk chain based on key hazards R1 R2 R3 R* R4 R5 R7 R6 R8 157 R3 R1 R4 R* R8 ...