Understanding the influence of multiple information sources on risk perception dynamics and evacuation decisions: An agent-based modeling approach

Evacuation is one of the most effective strategies to reduce risk during natural disasters. Although many studies have investigated factors affecting evacuation decisions (e.g., socio-economic, risk forecast, demographic, environmental cues, etc.), how all these factors interplay in forming the overall risk perception and evacuation decision is underexplored. Here, we present an agent -based model that leverages empirical evidence from post-disaster surveys to create evacuation tendencies of the agents (households) and integrates flood-related hazard risk, household socio-demographic factors, social network characteristics and decisions, and neighbors' decisions to dynamically evolve complex decision-making pattern during hurricane evacuation. We simulate the effect of multiple information sources and their perceived credibility on evacuation participa-tion by separately determining evacuation compliance (defined as evacuation from places where official mandatory evacuation order is issued) and shadow evacuation (defined as spontaneous evacuation from places where a mandatory order is not issued). We use socio-demographic data from U. S. Census Bureau, building footprint data from County Website, run off data from Stormwater Management Model (SWMM) of U.S. Environmental Protection Agency, and all other data were synthetically generated within the model. Our case study based on a community of Mi-ami-Dade County indicates that higher perceived credibility of hazard risk leads to higher evacu-ation compliance. We have also found that while social networks increase overall evacuation par-ticipation, they also increase shadow evacuation and higher trust on neighbor actions reduces evacuation rates. This study gives insights for emergency management to design appropriate strategies for providing hazard forecasts or communicating overall risk during disasters.

Automated summary

Evacuation is an effective strategy to reduce risk during natural disasters. However, the interplay of various factors in forming overall risk perception and evacuation decision is not well explored. This study uses an agent-based model to investigate the impact of flood-related hazard risk, household socio-demographic factors, social network characteristics, and neighbors' decisions on hurricane evacuation. The findings suggest that higher perceived credibility of hazard risk leads to higher evacuation compliance.