Research

Hybrid Platform Screening with Guillaume Thebaudin.

Abstract

Online marketplaces commonly employ a hybrid business model, wherein they are vertically integrated and sell their own products competing with third-party sellers on their platform. Free entry of these sellers may lead to the presence of harmful and illegal products, which consumers are not able to differentiate from safe ones. We extend the model of Anderson and Bedre-Defolie (2021) allowing the platform to invest in screening of sellers to remove illegal third-party products. We find that seller screening has an ambiguous effect on entry on the platform, and a condition for a platform to engage in screening is that it accommodates entry. Also, we find that more integrated platforms tend to screen less. Moreover, a platform conducting seller screening sets higher commission fees, the level of which can decrease in platform's degree of vertical integration in contrast with previous literature. From a welfare perspective, platforms invest too little in screening as compared to social optimum, and a regulation mandating higher screening intensity has an ambiguous effect on consumers’ surplus.

Draft available upon request!

Presented at internal seminars at Télécom Paris and Paris School of Economics, regulation and environment seminar at Paris School of Economics, EARIE 2023, CRESSE 2023 and AFREN (AFSE 2023)

Work in Progress

Advising Busy Decision Makers: Incentives in Costly Communication Settings Upcoming Talk: AFSE 2024

Abstract

We consider a principal-agent setting where perfect information is available yet never desirable. Modeling communication as a channel with an endogenous bit capacity, this article explores how constraints on message sets distort players' strategies. We prove the existence of an optimal mechanism that leads to the transmission of noisy yet truthful signals that enhance information quality while mitigating costs. The interactions between communication and incentive constraints create a moral hazard problem over the use of the channel. This induces a sub-optimal investment in communication and creates a setting similar to cheap talk with rational inattention when the principal is unable to commit. Our results suggest that simplicity matters more than precision when advising an overloaded decision-maker.

Draft available upon request!

*Presented at internal seminars at Télécom Paris and Paris School of Economics, IOEA 2022

Who lays down the law? Informational lobbying in the French assembly with Rosanne Logeart.

Draft coming soon!

Outreach in French

Quel prix pour vos données? Blog de la revue Regards Croisés sur l’Économie

Abstract

Le [23e numéro de Regards croisés sur l'économie](https://blogs.alternatives-economiques.fr/rcerevue/2019/08/23/quel-prix-pour-vos-donnees){:target="_blank"} , Donner ses données, contient toutes les clefs pour comprendre les débats du moment autour des données personnelles et de l'économie du numérique. Ce billet propose d'aller encore plus loin, en analysant le pouvoir que confère vos données aux entreprises qui les collectent.

Faut-il démanteler les GAFA? Entretien avec Pierre-Jean Benghozi Regards Croisés sur l’Économie, propos receuillis avec Sandra Desmettre

Abstract

Interview réalisé dans le cadre du [25e numéro de Regards croisés sur l'économie](https://www.cairn.info/revue-regards-croises-sur-l-economie-2019-2.htm){:target="_blank"} , La fabrique de la concurrence.