Michele BISCEGLIA will defend his thesis on Thursday 26th June, 2025 at 01:30 PM (Auditorium 6, bâtiment TSE and zoom)
Title: Essays in Applied Microeconomic Theory
Supervisors: Professors Jean Tirole and Patrick Rey
To attend the conference, please contact the secretariat of the TSE Doctoral school.
Memberships are:
- Jean TIROLE : TSE & IAST Honorary Chairman, UTC – TSE Supervisor
- Patrick Rey : Professor of Economics, Université Toulouse Capitole Co-supervisor
- Lucy White : Professor of Economics, Boston University - Questrom School of Business Rapporteure
- Julian Wright : Professor of Economics, National University of Singapore Rapporteur
Abstract :
This thesis contains three essays in applied microeconomic theory. It develops frameworks to advance the understanding of collusion in labor markets, digital platforms' strategies, and socially responsible investments, and derives policy implications.
The first chapter develops a theory of collusion in the presence of labor market power. In an oligopoly-oligopsony setting, a firm needs to increase its wage offers to recruit more workers and expand production, which dampens incentives to deviate from a collusive outcome. No-poaching and non-compete agreements, preventing a firm from hiring its rivals' workers, act as facilitating practices. As a result, labor market power increases firms' ability to collude, and collusion harms consumers and workers, underlining the need for antitrust authorities to monitor collusive behavior also in labor markets. However, if only wage collusion is monitored, or is prevented by enforcing a minimum wage, firms fiercely collude on prices, leaving consumers worse off than under unconstrained collusion.
The second chapter examines whether users receive their fair contribution to a digital ecosystem. The frequent accusations of self-preferencing and excessive platform fees leveled at dominant gatekeepers raise the issue of the standard these platforms should be held to. The important role played by two zero lower bounds on the pricing of core and complementary services in the setting of privately and socially optimal platform fees warrants the concerns about equity for business users. A simple “Pigouvian rule” for regulating access conditions ensures that business users appropriate their contribution to the ecosystem, promoting the right level of innovation; it does so by pricing the unpriced positive externality (ancillary benefit) enjoyed by a third-party seller that receives access to the consumer.
The third chapter analyzes the efficiency of socially responsible investing as a market-based mechanism to control firms' externalities. When responsible and profit-motivated investors interact, the former tend to concentrate on a subset of firms in the economy, while excluding others. This concentration of responsible capital can mitigate free-riding and coordination issues in the adoption of green technologies, but it can also create product market power and crowd out the green investments of excluded firms. If these unintended consequences dominate, aggregate green investments and welfare are larger in the absence of responsible investing. In equilibrium, responsible capital concentrates most when such concentration is least desirable.
