Date of Award

Summer 2023

Degree Type

Restricted to Claremont Colleges Dissertation

Degree Name

Political Science, PhD


School of Social Science, Politics, and Evaluation

Advisor/Supervisor/Committee Chair

Heather E. Campbell

Dissertation or Thesis Committee Member

Melissa Rogers

Dissertation or Thesis Committee Member

Brian Hilton

Terms of Use & License Information

Terms of Use for work posted in Scholarship@Claremont.

Rights Information

© 2023 Sekwen Kim


Environmental Policy, Event History Analysis, GIS, Public Policy Diffusion, Social Network Analysis

Subject Categories

Public Policy


Since the introduction of policy diffusion theory to understand how and why policies diffuse and are adopted across different jurisdictions, regions, or countries, the concept of policy adoption behavior, policy diffusion patterns, and the mechanism of policy diffusion have been extensively studied, and their application has been extended to other fields of policy research. Due to ambiguous economic benefits and the inability to observe the short-term effects of environmental policy, environmental policy diffusion has received less attention than the diffusion of other policies, despite a growing awareness of environmental concerns and an expanding application of policy diffusion in policy research. Due to the often-similar socioeconomic and political characteristics under state or county government, city-level policy diffusion has received less attention than state-level policy diffusion. This study integrates Social Network Analysis (SNA), Geographic Information System (GIS), and Event History Analysis (EHA) to provide a comprehensive understanding of mechanisms of micro-level, city-level environmental policy diffusion in the state of California. It has been empirically demonstrated that policy is not adopted arbitrarily but rather is diffused geographically through a channel of communication. Therefore, SNA and GIS provide useful analytical instruments for developing city-level environmental policy diffusion research, and EHA completes the argument regarding how environmental policy diffuses. This study's findings emphasize the importance of network structures, spatial proximity, and policy diffusion mechanisms in environmental policy diffusion. Specifically, this study finds that that the imitation mechanism is the policy diffusion mechanism that California's environmental policy diffusion followed. This study also finds that a political, whether citizens prefer Democratic presidential candidates, and two geographic factors, proximity to the Pacific Ocean and having a neighboring city that adopted the policy have a statistically significant positive effect on the adoption and diffusion of environmental policy in California. In addition, the use of an interdisciplinary approach that incorporated SNA, GIS, and EHA provides a comprehensive framework for analyzing and understanding environmental policy diffusion.