An Experiment Evaluating the Impact of Large-Scale, High-Payoff Vaccine Regret Lotteries

28 Pages Posted: 16 Aug 2021 Last revised: 27 Aug 2021

See all articles by Linnea Gandhi

Linnea Gandhi

University of Pennsylvania

Katherine L. Milkman

University of Pennsylvania - The Wharton School

Sean Ellis

University of Pennsylvania

Heather Graci

University of Pennsylvania

Dena Gromet

University of Pennsylvania

Rayyan Mobarak

University of Pennsylvania

Alison Buttenheim

University of Pennsylvania

Angela Duckworth

University of Pennsylvania - Department of Psychology

Devin G. Pope

University of Chicago - Booth School of Business

Ala Stanford

Black Doctors COVID-19 Consortium

Richard H. Thaler

University of Chicago - Booth School of Business; National Bureau of Economic Research (NBER)

Kevin Volpp

University of Pennsylvania - Perelman School of Medicine, Department of Medicine

Date Written: August 13, 2021

Abstract

We present a pre-registered experiment testing the effects of three, high-payoff (up to $50,000) vaccine regret lotteries in Philadelphia. In each drawing, residents of a randomly selected “treatment” zip code received half of the 12 lottery prizes (boosting their chances to 59-98x those of their neighbors). Our quasi-experimental results yield mixed estimates of the benefits of these lotteries for Philadelphia’s overall vaccination rate. Our experimental results, however, offer a causal estimate of the limited return on even high-odds vaccine lotteries. Difference-in-difference regressions estimate the first treated zip code experienced an insignificant 11% jump in vaccinations compared to control zip codes. Pooling results from all three, we do not detect significant benefits from treatment, and our 95% confidence interval bounds the benefits at 9%.

Note:
Funding Information: Funding for this project was provided by Flu Lab, the Behavior Change for Good Initiative at the University of Pennsylvania, and the Center for Health Incentives and Behavioral Economics at the University of Pennsylvania.

Declaration of Interests: Kevin G. Volpp is a part-owner of VAL Health, a behavioral economics consulting firm, all others have nothing to declare.

Ethical Approval Statement: Prior to implementation, the design for the Philly Vax Sweepstakes was reviewed and approved by the institutional review boards (IRBs) of the University of Pennsylvania and the City of Philadelphia. Our study’s analysis plan was pre-registered at osf.io/gxsa4.

Keywords: COVID-19, regret lottery, vaccination, vaccine hesitancy, field experiment, behavioral science, incentives

JEL Classification: D91, C93, I12, I18, Z18

Suggested Citation

Gandhi, Linnea and Milkman, Katherine L. and Ellis, Sean and Graci, Heather and Gromet, Dena and Mobarak, Rayyan and Buttenheim, Alison and Duckworth, Angela and Pope, Devin G. and Stanford, Ala and Thaler, Richard H. and Volpp, Kevin, An Experiment Evaluating the Impact of Large-Scale, High-Payoff Vaccine Regret Lotteries (August 13, 2021). Available at SSRN: https://ssrn.com/abstract=3904365 or http://dx.doi.org/10.2139/ssrn.3904365

Linnea Gandhi

University of Pennsylvania ( email )

Philadelphia, PA 19104
United States

Katherine L. Milkman (Contact Author)

University of Pennsylvania - The Wharton School ( email )

Philadelphia, PA 19104
United States

Sean Ellis

University of Pennsylvania ( email )

Philadelphia, PA 19104
United States

Heather Graci

University of Pennsylvania ( email )

Philadelphia, PA 19104
United States

Dena Gromet

University of Pennsylvania ( email )

Philadelphia, PA 19104
United States

Rayyan Mobarak

University of Pennsylvania ( email )

Philadelphia, PA 19104
United States

Alison Buttenheim

University of Pennsylvania

Philadelphia, PA 19104
United States

Angela Duckworth

University of Pennsylvania - Department of Psychology ( email )

3815 Walnut Street
Philadelphia, PA 19104-6196
United States

Devin G. Pope

University of Chicago - Booth School of Business ( email )

5807 S. Woodlawn Avenue
Chicago, IL 60637
United States

Ala Stanford

Black Doctors COVID-19 Consortium ( email )

Philadelphia, PA
United States

Richard H. Thaler

University of Chicago - Booth School of Business ( email )

5807 S. Woodlawn Avenue
Chicago, IL 60637
United States
773-702-5208 (Phone)
773-702-0458 (Fax)

National Bureau of Economic Research (NBER)

1050 Massachusetts Avenue
Cambridge, MA 02138
United States

Kevin Volpp

University of Pennsylvania - Perelman School of Medicine, Department of Medicine ( email )

Philadelphia, PA 19104
United States

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
596
Abstract Views
3,566
rank
57,347
PlumX Metrics