Examining the adaptation process of people's behavioral response to high gasoline costs

Many travel demand management policies are not effective in addressing traffic congestion. Policy makers assume people would actively respond to the policies that minimize social costs, but people might behave in a way to minimize their own costs - the costminimization hypothesis. The hypothesis implies that people tend to adopt lower-cost travel-related strategies, before moving to higher-cost ones if travel dissatisfaction persists. Travel behaviour studies have yet to substantiate the hypothesis. This study conducted several statistical tests using the 2008-2009 data in Minneapolis-St. Paul metropolitan area. The analysis on the adoption of different groups of travel-related strategies offer supportive evidence for the hypothesis: the adoptions are interdependent. An examination of adoption time confirms that people tend to first seek mitigation from low-cost strategies, before moving to mediumor high-cost strategies. Overall, this study substantiates the discrepancy between policy assumptions and people's behavior responses, which helps explain the limited effectiveness of travel demand management policies.