Ship collision is a major type of accident in waterway transportation, with considerable annual occurrence
that always causes serious casualty. Among the evidences that can facilitate the investigation,
AIS data recorded during the context of the collision are highly informative. This paper exploits the contextual
AIS data in a coupled spatial–temporal perspective. With the discrete waypoints specified by the
AIS data, the trajectories of the colliding ships are regenerated with three reasoning respects: (1) the con-
flict-resolution envisioned by each ship in the collision-inducing scenario when the two ships are drawing
near; (2) to what extent the two ships can make situation assessment and the de facto maneuvers
exerted to steer the ships; (3) how to evaluate the decision quality of the steering process and how to
measure the consistency between the subjective endeavors and the objective results in the context of
bilateral anti-collision maneuvers. According to the periodical nature of the AIS data, time is slotted into
slices to make temporal analysis and to sketch out the decision sequences made by both ships. Fuzzy set
method is adopted to estimate the quality of the decisions, and a Dempster–Shafer Theory (DST) based
method is employed to fuse the discernment in time domain and in spatial domain, so that an overall
impact of the behavior of both ships can be calculated. The current paper presents a microscopic analytical
scheme for a two-vessel collision accident investig