Mutually Reinforcing Relationships Between Bicycling and Infrastructure

Abstract

Researchers have long sought evidence about whether dedicated bicycling infrastructure induces people to cycle, based on a supply-driven assumption that providing infrastructure causes the behavior change. However, supply inducing demand is only one of four theoretical relationships between bicycling and infrastructure. The aims of this research are twofold: 1. Develop a theoretical framework to identify and evaluate all of the possible relationships between bicycling and infrastructure and describe how these factors reinforce one another to shape diffusion of bicycling and infrastructure in cities; and 2. Develop and execute a research plan to empirically model selected hypotheses within the theoretical framework. The empirical portion of the dissertation tests the hypotheses that (1) bicycling infrastructure supply induces bicycling demand, and (2) bicycling demand induces additional demand. The research uses a series of cross-sectional tests at multiple points in time as well as lagged variable models to add a layer of temporal precedence to our otherwise cross-sectional understanding of associations between bicycling and infrastructure. The findings show persistent associations between infrastructure and bicycling over time, across geographies, and at both the individual and aggregate level. The association between bicycling and additional bicycling holds over time at the individual household level and for bike share membership. However, the tests failed to find evidence of bike share stations and activity affecting general population cycling rates. This dissertation provides a roadmap for future research into feedback loops between bicycling and infrastructure. It additionally provides practitioners with guidance on both the strengths and limitations of both infrastructure provision and socially-focused bicycling initiatives. Like most bicycling research, this dissertation is limited by the quality of data available for both bicycling behavior and infrastructure supply. Neither the data nor the tests performed are rigorous enough to infer causality; instead, the findings add strength and nuance to the existing body of literature.