Dear colleagues,

you are all invited to participate in the following seminar organized by QFinLab – Department of Mathematics, Politecnico di Milano.

Monday, 9 June 2025, 12.15-13.15

Seminar room, third floor, building 14, Via Bonardi 9, Milano (Leonardo Campus)

Marco Tolotti (Università Ca’ Foscari Venezia)

Title: Market Dynamics, Learning, and the Equity Premium Puzzle in an Agent-Based Model of Information Acquisition.

Abstract: We analyze a financial market with a large number of investors who use an imitation-based learning mechanism to choose among various strategies that differ in the amount and quality of information they incorporate. Agents’ strategies evolve through a straightforward learning mechanism in which traders occasionally imitate more successful strategies adopted by peers they encounter. In this context, equilibrium is defined as a state where investors, on average, win half the time and lose in the remaining periods.
Through an agent-based model, we show that at equilibrium, most investors rely on a limited number of strategies. In most scenarios, two strategies dominate: overly cautious traders, who hold little equity and capture the largest market share, and informed traders, who achieve higher average profits. Our model can help to justify the existence of an equity premium puzzle: in equilibrium, the higher mean profit of informed investors is associated with a median profit that is equal to that of more prudent or misinformed investors.

The organizers: Michele Azzone and Alessandro Calvia.