Target vehicle identification for border safety with modified mutual information

In recent years border security has been identified as a critical part of homeland security. The Department of Homeland Security monitors vehicles entering and leaving the country at land borders. Some vehicles are targeted to search for drugs and other contraband. Customs and Border Protection agents believe that vehicles involved in illegal activity operate in groups. If the criminal links of one vehicle are known then their border crossing patterns can be used to identify other partner vehicles. We perform this association analysis by using mutual information (MI) to identify pairs of vehicles that are potentially involved in criminal activity. Domain experts also suggest that criminal vehicles may cross at certain times of the day to evade inspection. We propose to modify the MI formulation to include this heuristic by using cross-jurisdictional criminal data from border-area jurisdictions.