Yann Bramoullé

  • Faculty

Aix-Marseille Université
5-9 Boulevard Bourdet, CS 50498
13205 Marseille Cedex 1
Phone: +33 (0)4 13 55 25 34 / +33 (0) 413 94 20 06
Research professor
Research themes:
Environmental economics
Game theory and social networks
University of Maryland
Title length, Yann Bramoullé and Lorenzo Ductor, Journal of Economic Behavior & Organization, Volume 150, Issue C, pp. 311-324, 2018

We document strong and robust negative correlations between the length of the title of an economics article and different measures of scientific quality. Analyzing all articles published between 1970 and 2011 and referenced in EconLit, we find that articles with shorter titles tend to be published in better journals, to be more cited and to be more innovative. These correlations hold controlling for unobserved time-invariant and observed time-varying characteristics of teams of authors.

Altruism in Networks, Renaud Bourlès, Yann Bramoullé and Eduardo Perez-Richet, Econometrica, Volume 85, Issue 2, pp. 675-689, 2017

We provide the first analysis of altruism in networks. Agents are embedded in a fixed network and care about the well‐being of their network neighbors. Depending on incomes, they may provide financial support to their poorer friends. We study the Nash equilibria of the resulting game of transfers. We show that equilibria maximize a concave potential function. We establish existence, uniqueness of equilibrium consumption, and generic uniqueness of equilibrium transfers. We characterize the geometry of the network of transfers and highlight the key role played by transfer intermediaries. We then study comparative statics. A positive income shock to an individual benefits all. For small changes in incomes, agents in a component of the network of transfers act as if they were organized in an income‐pooling community. A decrease in income inequality or expansion of the altruism network may increase consumption inequality.

The Oxford Handbook of the Economics of Networks, Yann Bramoullé, Andrea Galeotti and Brian Rogers (Eds.), 2016-04, 857 pages, Oxford University Press, 2016

The Oxford Handbook of the Economics of Networks represents the frontier of research into how and why networks they form, how they influence behavior, how they help govern outcomes in an interactive world, and how they shape collective decision making, opinion formation, and diffusion dynamics. From a methodological perspective, the contributors to this volume devote attention to theory, field experiments, laboratory experiments, and econometrics. Theoretical work in network formation, games played on networks, repeated games, and the interaction between linking and behavior is synthesized. A number of chapters are devoted to studying social process mediated by networks. Topics here include opinion formation, diffusion of information and disease, and learning. There are also chapters devoted to financial contagion and systemic risk, motivated in part by the recent financial crises. Another section discusses communities, with applications including social trust, favor exchange, and social collateral; the importance of communities for migration patterns; and the role that networks and communities play in the labor market. A prominent role of networks, from an economic perspective, is that they mediate trade. Several chapters cover bilateral trade in networks, strategic intermediation, and the role of networks in international trade. Contributions discuss as well the role of networks for organizations. On the one hand, one chapter discusses the role of networks for the performance of organizations, while two other chapters discuss managing networks of consumers and pricing in the presence of network-based spillovers. Finally, the authors discuss the internet as a network with attention to the issue of net neutrality. Contributors to this volume - Daron Acemoglu Sinan Aral Lori Beaman Francis Bloch Vincent Boucher Yann Bramoulle Emily Breza Antonio Cabrales Arun Chandrasekhar Thomas Chaney Syngjoo Choi Daniele Condorelli Wouter Dessein Marcin Dziubinski Nick Economides

Introduction to the Handbook, Yann Bramoullé, Andrea Galeotti and Brian W. Rogers, In: Oxford Handbook on the Economics of Networks, Yann Bramoullé, Andrea Galeotti and Brian W. Rogers (Eds.), 2016-04, pp. 3-9, 2016


Games Played on Networks, Yann Bramoullé and Rachel Kranton, In: Oxford Handbook on the Economics of Networks, Yann Bramoullé, Andrea Galeotti and Brian W. Rogers (Eds.), 2016-04, pp. Chap.5, 2016



Manufacturing Doubt, Caroline Orset and Yann Bramoullé, Journal of Environmental Economics and Management, Forthcoming

In their efforts to affect regulations, firms
have developed specific strategies to exploit scientific uncertainty. They
have manufactured doubt by hiring and funding dissenting scientists, by
producing and publicizing favorable scientific findings and by generally
concealing their involvement in biased research. We propose a new model to
study the interplay between scientific uncertainty, firms' miscommunication
and public policies. The government is benevolent but populist, and
maximizes social welfare as perceived by citizens. The industry can produce
costly reports showing that its activity is not harmful. Citizens are
unaware of the industry's miscommunication. We first characterize the
industry's optimal miscommunication policy. The industry notably ceases
miscommunicating abruptly when scientists' belief reaches a critical
threshold. We identify a natural condition under which miscommunication is
stronger under a tax on emissions than under command and control. We then
analyze research funding. A populist government may support research to
enable firms to falsely reassure citizens. Establishing an independent
research agency helps limit the welfare losses induced by populist policies.