where \(\alpha_{th}\) is the sensitivity threshold that the driver can spot. \(\alpha_{sv}, \alpha_{bv}\) are the aggressiveness of the subject vehicle and the background vehicle respectively. \(\kappa_1, \kappa_2, \kappa_3\) are the sensitivity parameters. For the decision-making algorithm, the probability in (9) is replaced by the expectation of the Dirichlet distribution defined by