Residential Parking Supply Has a Stronger Influence on Household Travel Choices Relative to a Neighborhood’s Walkability and Access to Transit

A large volume of research suggests that neighborhood attributes such as public transportation access, residential density, and walkability can have important impacts on people’s travel, carbon footprint, and employment opportunities. More often than not, however, the research conducted on this topic is subject to “self-selection bias.” For example, people who prefer to walk and ride transit are likely to move to neighborhoods that support these choices,while those who prefer to drive instead move to places with nearby highway access and ample parking.To overcome these biases, a research team at the University of California, Santa Cruz surveyed successful applicants to San Francisco’s affordable housing lotteries about their transportation choices and employment. In San Francisco, nearly all new housing developments with ten or more residential units must provide affordable housing units at below-market rates. The units are normally allocated to qualifying households through city-run lotteries. Thechances of winning a lottery are small — less than two percent — and so, not surprisingly, households are notselective about which lotteries they enter. Analysis of lottery application data shows that applicants do not appear toenter any particular lottery based on where they would endup living, or if the residence has ample parking, or based onthe neighborhood’s walkability or transit accessibility