Department of Operations, Information and Decisions, The Wharton School, University of Pennsylvania, Philadelphia, PA, USA.
Behavior Change for Good Initiative, The Wharton School, University of Pennsylvania, Philadelphia, PA, USA.
Nat Hum Behav. 2022 Nov;6(11):1515-1524. doi: 10.1038/s41562-022-01437-0. Epub 2022 Sep 1.
Lotteries have been shown to motivate behaviour change in many settings, but their value as a policy tool is relatively untested. We implemented a pre-registered, citywide experiment to test the effects of three high-pay-off, geographically targeted lotteries designed to motivate adult Philadelphians to get their COVID-19 vaccine. In each drawing, the residents of a randomly selected 'treatment' zip code received half the lottery prizes, boosting their chances of winning to 50×-100× those of other Philadelphians. The first treated zip code, which drew considerable media attention, may have experienced a small bump in vaccinations compared with the control zip codes: average weekly vaccinations rose by an estimated 61 per 100,000 people per week (+11%). After pooling the results from all three zip codes treated during our six-week experiment, however, we do not detect evidence of any overall benefits. Furthermore, our 95% confidence interval provides a 9% upper bound on the net benefits of treatment in our study.
彩票已被证明可以在多种情况下促使行为发生改变，但作为一种政策工具，其价值尚未得到充分验证。我们实施了一项预先注册的、全市范围的实验，以测试三种高收益、有针对性的彩票的效果，这些彩票旨在激励成年费城人接种 COVID-19 疫苗。在每次抽奖中，随机选择的“治疗”邮政编码的居民将获得一半的彩票奖金，使他们的中奖几率比其他费城人高 50 到 100 倍。第一个接受治疗的邮政编码引起了相当多的媒体关注，与对照邮政编码相比，疫苗接种人数可能略有增加：平均每周接种人数每周增加约 61 人/每 10 万人 (+11%)。然而，在汇总了我们为期六周的实验中治疗的所有三个邮政编码的结果后，我们没有发现任何整体收益的证据。此外，我们的 95%置信区间为我们研究中治疗的净收益提供了 9%的上限。
