Modeling the Cooperation Network Formation Process for Evacuation Systems Design in Disaster Areas with a Focus on Japanese Megadisasters

Abstract

By treating human relationships as networks, disaster response planners can capture the features of cooperative behaviors between residents, providing valuable insights for effective evacuation planning. In this paper, the writers outline residents’ evacuation behaviors during the 2011 Great East Japan earthquake and the resulting nuclear disaster and tsunami. An analysis of these evacuation behaviors shows the significance of cooperation between residents and of problems caused by two types of bias: normalcy and majority syncing. Next, the writers describe how residents’ cooperation behaviors accumulate to form cooperation networks and apply the fitness model to the formation of these networks. A case study of network formation in response to a mudslide disaster in the city of Niihama in 2004 is provided. The writers estimate the fitness parameters and analyze the network formation process and structure on the basis of the distribution of the fitness parameters and show the scale-free characteristics of the evacuation phase of this disaster. Disaster response planning can take into consideration the scale-free networks that form around central and bridging players and acknowledge the importance of the role of cooperation behaviors in disasters.