The Homeland Security Advisory System (HSAS) lacks specific measures for rational decision making, and mathematical modeling has not been applied to capture the interaction between defender and attacker in terrorist attacks. An efficient emergency response system must determine how and when to alert and advise the critical and appropriate response agents to the danger of terrorist attacks, particularly when available resources are limited in an urban environment. We propose a framework for HSAS that incorporates two game theory models designed to advise response agents when raising the threat advisory level. In the first step, the interactive behaviors between the elements or participants of the multi-emergency event and the district response agent are modeled and analyzed as a noncooperative game, after which the terrorist threat value (TTV) is derived from the mixed strategy Nash equilibrium. In the second step, the TTV is used to compute the Shapley value of all district response agents for five different threat levels; a fair allocation of response agents based on the Shapley value creates a minimum set of resource deployment costs. Simulation results show that the emergency manager can use this framework to quantitatively evaluate the terrorist threat to each response agent and easily discover where response agents are most at risk within the five threat levels.
JOURNAL OF HOMELAND SECURITY AND EMERGENCY MANAGEMENT