Fig. 6: The impact of the intensity of the port fee difference policy combination on the evolutionary strategies of all parties.

a The impact of port fee difference policy combination on the evolution process; b the impact of port fee difference policy combination on the probability of x making a decision over time; c the impact of port fee difference combination on the probability of y making a decision over time; d the impact of port fee difference policy combination on the probability of z making a decision over time.