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Hayeon Jeong

@hjeong88

Environmental econ, Behavioral econ, Air pollution Website: https://sites.google.com/view/hayeonjeong

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06.11.2025
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Latest posts by Hayeon Jeong @hjeong88

Policy takeaway💫
These findings highlight that, even when a policy effectively reduces pollution during regulated hours, unintended consequences during non-regulated hours should also be considered in policy evaluation.

12.11.2025 22:07 👍 1 🔁 0 💬 0 📌 0
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Health Implications⚕️
Increased policy avoidance translates into health costs. More stringent events led to larger increases in air pollution during non-crackdown hours. Using an exposure–response function and real-time hourly population data, I provide rough estimates of the resulting health costs

12.11.2025 22:07 👍 0 🔁 0 💬 1 📌 0
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Key Result 2🗝️
Moreover, the magnitude of policy avoidance is proportional to the degree of policy stringency when compared 'across' multiple policy events. In other words, the more stringent the policy event was, the more increase in policy avoidance we see.

12.11.2025 22:07 👍 1 🔁 0 💬 1 📌 0
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Key Result 1🗝️
Empirically, I confirm that this theoretical prediction holds. Each policy-strengthening event is associated with a rise in policy avoidance behavior: traffic during non-regulated hours increased for the treated group relative to the control group following each policy event.

12.11.2025 22:07 👍 0 🔁 0 💬 1 📌 0
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Theoretical prediction✏️
The theoretical model predicts that the number of policy avoiders—individuals who legally circumvent the policy by exploiting loopholes (analogous to tax avoidance, in contrast to tax evasion)—increases as the policy becomes more stringent.

12.11.2025 22:07 👍 0 🔁 0 💬 1 📌 0

I also use a unique dataset of hourly, road-level, and vehicle-emissions–category-level traffic data to provide direct evidence of policy avoidance. I answer my research question both theoretically and empirically.

12.11.2025 22:07 👍 1 🔁 0 💬 1 📌 0
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Contribution📖
Existing works typically treat policy implementation as a 'dichotomous' event when assessing policy effectiveness. Instead, my paper leverages several policy-intensifying events, and examines how the magnitude of policy avoidance evolves across multiple rounds of policy strengthening.

12.11.2025 22:07 👍 0 🔁 0 💬 1 📌 0

How do I do it?🤔
I exploit the gradual intensification of Seoul’s low-emission-zone driving ban on high-polluting vehicles—an increasingly common policy tool to reduce urban pollution worldwide. I focus on shifts in travel time to non-regulated hours as a form of policy avoidance behavior.

12.11.2025 22:07 👍 0 🔁 0 💬 1 📌 0
Preview
Hayeon Jeong Hayeon Jeong Ph.D. in Sustainable Development Columbia University

🔗https://drive.google.com/file/d/1CUvPzBF7pw8HpcoDYvyuO8czfaRlhzBf/view?usp=drive_link

Website: sites.google.com/view/hayeonj...

Research Areas: Environmental Economics, Behavioral Economics, Applied Microeconomics

12.11.2025 22:07 👍 2 🔁 0 💬 1 📌 0
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I'm happy to share my #JMP on the relationship between policy intensity and effectiveness!

It challenges the idea that stricter policies are always more effective by showing that policy avoidance rises with stringency during the early period of implementation.
🧵👇
#Econsky #EconJobMarket #EconJMP

12.11.2025 22:07 👍 15 🔁 2 💬 1 📌 2