Capacci Sara, Mazzocchi Mario, Shankar Bhavani
Department of Economics, University of Bologna, Rimini, Italy.
Department of Statistical Sciences, University of Bologna, Bologna, Italy.
J Policy Anal Manage. 2018;37(1):88-111. doi: 10.1002/pam.22032.
This paper estimates the effect of the 2005 vending machine ban in French secondary schools on nutrient intakes and on the frequency of morning snacking at school. Using data before and after the ban, and exploiting the discontinuity associated with the age-dependent exposure to the ban, we specify a difference-in-differences regression discontinuity design. Since the relationship between age-at-interview and school level is not precise, we introduce fuzziness in the model. We find that the ban has generated a 10-gram reduction in sugar intakes from morning snacks at school, and a significant reduction in the frequency of these morning snacks. However, we find no evidence that the intervention affects total daily intakes, and our results are suggestive of compensation effects.
本文估计了2005年法国中学自动售货机禁令对营养摄入量以及学校上午吃零食频率的影响。利用禁令前后的数据,并利用与年龄相关的禁令暴露所关联的不连续性,我们指定了一个双重差分回归不连续性设计。由于访谈时的年龄与学校级别之间的关系不精确,我们在模型中引入了模糊性。我们发现,该禁令使学校上午零食的糖分摄入量减少了10克,并且这些上午零食的频率显著降低。然而,我们没有发现证据表明该干预措施会影响每日总摄入量,并且我们的结果表明存在补偿效应。