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Many policies in the US are determined locally, e.g., at the county-level. Local policy regimes provide flexibility between regions, but may become less effective in the presence of geographic spillovers, where populations circumvent local restrictions by traveling to less restricted regions nearby. Due to the endogenous nature of policymaking, there have been few opportunities to reliably estimate causal spillover effects or evaluate their impact on local policies. In this work, we identify a novel setting and develop a suitable methodology that allow us to make unconfounded estimates of spillover effects of local policies. Focusing on California’s Blueprint for a Safer Economy, we leverage how county-level mobility restrictions were deterministically set by public COVID-19 severity statistics, enabling a regression discontinuity design framework to estimate spillovers between counties. We estimate these effects using a mobility network with billions of timestamped edges and find significant spillover movement, with larger effects in retail, eating places, and gyms. Contrasting local and global policy regimes, our spillover estimates suggest that county-level restrictions are only 54% as effective as statewide restrictions at reducing mobility. However, an intermediate strategy of macro-county restrictions—where we optimize county partitions by solving a minimum k-cut problem on a graph weighted by our spillover estimates— can recover over 90% of statewide mobility reductions, while maintaining substantial flexibility between counties.
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Analyzing spillovers from food, energy and water conservation behaviors using insights from systems perspective
Abstract Spillover effects are considered important in evaluating the impacts of food, energy and water (FEW) conservation behaviors for limiting global greenhouse gas emissions and climate change. Failure to account for all possible spillovers, or indirect and unintended results of an intervention, not only obscures valuable information pertaining to the dynamic interactions across domains but also results in biased estimates. In this study, we first systematically reviewed articles that investigate the idea that the performance of one pro-environmental behavior influences the conduct of subsequent behaviors(s) from the FEW domains. From our review of 48 studies in the last decade, we note that a big part of the discussion on spillover concerns the nature and direction of causal relationships between individual FEW conservation behaviors. We identify a critical gap in the literature regarding the distinction between spillover effects caused by the interventions as distinct from those caused by the primary behaviors. Next, we conducted a quantitative meta-analysis of the reviewed empirical studies to find a modest but overall positive spillover effect. Finally, we reviewed the theoretical and methodological plurality in the FEW spillover literature using a systemic thinking lens to summarize what is already known and identify future challenges and research opportunities with significant policy implications.
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- Award ID(s):
- 1639342
- PAR ID:
- 10486650
- Publisher / Repository:
- Cambridge University Press
- Date Published:
- Journal Name:
- Behavioural Public Policy
- Volume:
- 7
- Issue:
- 3
- ISSN:
- 2398-063X
- Page Range / eLocation ID:
- 773-807
- Subject(s) / Keyword(s):
- pro-environmental behaviors spillover effects food, energy and water nexus behavioral spillover systems approach
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/bpp.2022.41
