Breaking Habits: The Effect of the French Vending Machine Ban on School Snacking and Sugar Intakes
利用断点回归设计，估计2005年法国中学自动售货机禁令对在校上午零食糖分摄入和频率的影响，发现糖分摄入减少10克，但总日摄入量无显著变化，存在补偿效应。
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.