Gonzalo Ballestero

Gonzalo Ballestero

I am a Ph.D. candidate in Economics at Penn State University.

I am an applied microeconomist working at the intersection of empirical market design, AI behavioral science, and industrial organization.

Here you can find my curriculum vitae.

You can contact me at gballestero@psu.edu.

Visit our AI and the Economy Initiative.

Working Papers

Strategic Algorithmic Monoculture: Experimental Evidence from Coordination Games, April 2026 [ArXiv]
with Hadi Hosseini, Samarth Khanna, and Ran I. Shorrer

AI agents increasingly operate in multi-agent environments where outcomes depend on coordination. We distinguish primary algorithmic monoculture (baseline action similarity) from strategic algorithmic monoculture, whereby agents adjust similarity in response to incentives. We implement a simple experimental design that cleanly separates these forces, and deploy it on human and large language model (LLM) subjects. LLMs exhibit high levels of baseline similarity (primary monoculture) and, like humans, they regulate it in response to coordination incentives (strategic monoculture). While LLMs coordinate extremely well on similar actions, they lag behind humans in sustaining heterogeneity when divergence is rewarded.

Publications

Algorithmic Collusion under Sequential Pricing and Stochastic Costs, June 2026. [SSRN] | [Code]
Forthcoming at the International Journal of Industrial Organization

The use of pricing algorithms raises concerns about algorithmic collusion. This paper considers a sequential pricing model where marginal cost fluctuates over time. I find that Q-learning algorithms autonomously collude even under cost uncertainty. Collusion is sustained by strategies that involve reward-punishment schemes. It suggests that cost uncertainty is not an obstacle to autonomous algorithmic collusion.

Work in Progress

Centralized Admission Mechanisms and International Migration

Information Frictions and Biased Beliefs in Centralized Admissions

Policy Briefs

Cheating in the Medical Residency Entrance Exam (in Spanish), July 2025

The Medical Match in Argentina: Toward More Equitable Access (in Spanish), June 2025
with Mariana Gudiño and Nahir Lera

Resources

A Practitioner's Guide to Agentic AI Tools: From Chatbot to Autonomous Agents, April 2026