Calendrier du 05 novembre 2018
Roy Seminar (ADRES)
Du 05/11/2018 de 17:00 à 18:30
Salle R1-09, Campus Jourdan, 48 boulevard Jourdan, 75014 Paris
YANG Li (ZEW Mannheim and WIL)
Information order in monotone decision problems under uncertainty
écrit avec Junjie Zhou
This paper examines the robustness of Lehmann’s ranking of experiments (Lehmann, 1988) for decisionmakers who are uncertainty-averse à la Cerreia-Vioglio et al. (2011). Assuming commitment, the main result says for all uncertainty-averse indices satisfying some mild assumptions, Lehmann’s informativeness ranking is equivalent to the induced uncertainty-averse value ranking of experiments for all agents with single-crossing vNM utility indices. Our finding suggests that Lehmann’s ranking can be a useful enrichment of Blackwell’s ranking for monotone decision problems even if ambiguity is present.
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Régulation et Environnement
Du 05/11/2018 de 12:00 à 13:00
salle R1-13, campus Jourdan - 75014 Paris
DELMAS Magali (Maggie) (UCLA)
Sustainable Practices and Wine Quality: Is there value in Certification?
écrit avec Olivier Gergaud
More and more wineries are using third-party eco-certification, such as organic or biodynamic certification, to communicate their sustainable practices. At the same time some wineries are adopting sustainable practices without third party certification. In France for example, some wineries self-proclaim themselves "Viticulture Raisonnée" (reasoned viticulture), a flexible approach to sustainability devoid of the rigidity of third party certification. The presence of these different sustainable practices raises the question of their comparative value. While previous research estimates that third party eco-certification leads to increased quality as evaluated by experts, it is unknown whether non-certified sustainable practices are also associated with quality improvements. Evaluating the impact of non-certified sustainability practices on quality is challenging due to the difficulty of identifying such practices. In this paper, we use French data on experts' quality ratings from Gault Millau, Gilbert Gaillard and Bettane Desseauve, to compare the ratings of self-proclaimed sustainable wines to third party eco-certified wines and conventional wines. A total of 140,690 wines is analyzed. Preliminary findings based on different matching techniques indicate that self-proclaimed sustainable wines are of lower quality than conventional wines, while eco-certified wines are of higher quality than conventional wines. This suggest that non certified practices could be associated with greenwashing.
JEL Classification: L15, L66; Q5