Learning and Behavioural Spillovers of Nutritional Information
研究印度昌迪加尔城市贫民窟中营养信息的社会学习与模仿溢出效应，发现未直接接受干预的母亲通过邻里互动提升了营养知识、改变了饮食行为并降低了食品支出，对政策制定和实验设计有重要启示。
This paper provides evidence for informational spillovers within urban slums in Chandigarh, India. I identify three groups, a treatment group, a neighbouring spillover group, and a non-adjacent pure control group. Mothers of children (aged three to six years) enrolled in government day-care centres are given recipe books in the treatment group to reduce malnutrition in their children. Spillovers to neighbouring (untreated) mothers can be through social learning or imitation. Results from a difference-in-differences analysis show that nutritional knowledge measured through a quiz increases among neighbouring untreated mothers relative to a control group. Neighbouring mothers exhibit learning spillovers, changes in dietary behaviour and a reduction in food expenditure regardless of their level of literacy. Spillovers not only raise the cost effectiveness of health information programmes but are important to consider when designing an experiment as causal effects of treatments can be attenuated if the spillover group is used as a control group.