EVALUATION WITH INADEQUATE DATA: THE IMPACT OF THE FRENCH VENDING MACHINE BAN

We estimate the effects of the 2005 ban on vending machines in French schools using the 1998 and 2006 INCA nutrition surveys. These surveys contain no information on the presence of vending machines in schools attended by respondents, but the adoption of a Difference-in-Difference design, and a Regression Discontinuity Design enable us to obtain indirect estimates of the policy impact. Results are consistent and suggest that the measure has had a small but significant impact on teenager nutrition, especially in terms of reduced fat intakes.