Association for Public Policy Analysis & Management

Research in policy diffusion often assumes that diffusion is a stationary process, where each governing unit responds to other jurisdiction’s adoptions identically. While this approach has been tantamount in developing and advancing diffusion theory, assuming all geographic units behave the same way may not reflect the reality of state and local governments. When considering a specific policy, some jurisdictions may compete, others may learn or emulate one another, while some may not respond to neighboring adoptions at all. In this study, we develop a new non-stationary approach to examining diffusion. This approach will better enable researchers to evaluate where diffusion is occurring and what diffusion theory is most applicable to specific geographical locations. Using the first application of the Geographically Weighted Logistic Regression (GWLR) to policy diffusion research, we explore the intra-metropolitan diffusion of local climate change policies in Southern California. This study adds to the body of diffusion research by developing a new diffusion theoretical application, applying a new methodological approach, and conducting one of the first intra-metropolitan diffusion studies at the local level.