Mode Choice, the Built Environment, and Consumer Behavior: Insights from Davis, CA

Growing concerns about climate change and traffic congestion are motivating policymakers to find ways to encourage sustainable travel options. In the U.S., where 88% of shopping trips are made by car, research identifying the factors that influence shopping mode choice can provide insight into ways to divert some of these trips to more sustainable alternatives. This thesis examines the relationship between the built environment, retail shopping mode choice, and consumer behavior. The objective of this study is twofold. First, to examine which factors influence mode choice to three different shopping destination types -- downtown, strip center, and big box - in Davis, CA. Second, to examine how shopping behavior in downtown Davis varies between bicyclists and motorists -- two groups that are in perpetual competition for parking spaces and other infrastructure accommodations. I use data from two cross-sectional online surveys conducted in 2009 and 2010 with a total of 2,043 respondents that asked questions about recent shopping trips. To address the first question, I estimate binary logit models for choosing to use an active travel mode to each of the three destination types. I find that distance to shopping destination and bicycling enjoyment are the primary determinants of choosing active travel modes, while socio-demographic characteristics play a smaller role. Perceptions of the convenience of using different modes to shop vary significantly across destination types and correspond to observed mode shares. However, the results suggest that while distinct factors influence mode choice at the different destination types, simple infrastructure changes to the destination are not enough to encourage mode shift. To address the second question, I first compare shopping trip frequency and spending of shoppers who bicycled downtown to those who used a car to test for significant differences and then estimate binary logit models for bicycling downtown or not to identify factors significant in choosing to bicycle to shop. I find that customers who biked on their most recent trip downtown spent slightly higher amounts on average on their purchases each trip than their auto-driving counterparts, and that they made more frequent shopping trips, thus contributing larger amounts of money to downtown establishments than customers travelling by car. These findings help support the case for converting some auto infrastructure to bicycling infrastructure.