Calendrier du 18 mars 2019
Roy Seminar (ADRES)
Du 18/03/2019 de 17:00 à 18:30
Salle R1-09, Campus Jourdan, 48 boulevard Jourdan, 75014 Paris
FLECKINGER Pierre (Ecole des Mines de Paris)
The Incentive Properties of Collective Reputation
écrit avec Wanda Mimra and Angelo Zago
Collective Reputation is often viewed as creating free-riding and impeding quality provision. It is however a widespread and often deliberate choice of producers. We provide new explanations for this based on group incentives. Heterogeneous producers whose costs are imperfectly known need to provide effort to produce high quality. The demand side a priori does not observe the true quality, but high quality can be detected with some probability, reflecting e.g. expert inspections, awards, labeling and the regulatory framework. Unidentified products are otherwise pooled together according to the collective reputation structure, i.e. grouping of producers. In the unique equilibrium, each group is subject to internal free-riding by their higher-cost members. We find however that grouping producers can also increase incentives and yield higher quality and welfare than individual reputation, because free-riding under collective reputation might be less severe than own-reputation milking under individual reputations. We also show that admission thresholds with a small elite always improves upon full collective reputation. Despite potentially higher producers' surplus, any group with collective reputation however unravels in absence of transfers. Nevertheless, we exhibit simple type-independent and budget-balanced contracts under collective reputation that implement the first best.
Régulation et Environnement
Du 18/03/2019 de 12:00 à 13:00
salle R1-13, campus Jourdan, 75014 Paris
BECERRA VALBUENA Luis ()
Do local ENSO events affect air quality and health in Bogotá ?
écrit avec Professor Jorge
We aim to analyze if, for the case of Bogota, the ENSO events (El Niño and la Niña) have an effect on health via weather and air quality. To our knowledge, no one seems to have investigated further the ENSO events on weather, how this relates with the concentration of air pollutants and the impact it could have on health outcomes. The question seems more relevant now as an increase in intensity and frequency of El Niño phenomena are expected in the coming years (see chapter 3 of last report Global Warming of 1.5 Celsius degrees the Intergovernmental Panel of Climate Change). The paper is purely empirical and uses a large database for a period running from 1997 to 2015 for different stations measuring pollutants as well as meteorological and weather variables along the city. The data are rich (by day and hour in many cases) and allow to do a unique analysis. Information of health outcomes come from a data-set of health centers along the city, with information of respiratory and cardiovascular diseases between 2012 to 2015. Information of births and deaths (weight at birth, height at birth, weeks of gestation, etc) is available from 1997 to 2015. Information of the ENSO events is publicly available by month since 1950.
As a first step, we have estimated the effects of ENSO events on weather and on pollutants hour by hour, using those phenomena as a quasi-experiment; this has allowed us to understand better at which time of the day, weather and pollutant factors are highly or less affected by ENSO events. In terms of weather, the effect goes in the expected direction, with higher temperature in El Niño and higher rain in La Niña. However, the effects on weather variables tend to be higher during La Niña than during El Niño, and in both cases, the maximum effects happen during the afternoon peak, in comparison with the morning. In terms of pollution, El Niño brings higher temperatures, and pollutants such as particulate matter and CO increase during these events, in peak hours. However, La Niña brings more rain which could help to clean those contaminants. Importantly, peak hours of transport matter to increase pollution, and ENSO events are more relevant during this time. The hours of the day when the effects are more important should be considered in the health equation. The step to follow will be to test the potential effects this could have on health costs, and to estimate the economic cost of these phenomena (on QUALYS-DALYS).