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6 Stan. Computational Antitrust 1 (2026)

handle is hein.journals/stfdcmp6 and id is 1 raw text is: 



















                                ARTICLE



    Smart Agent-Based Modelling with LLMs:

 Leveraging Large Language Models for a Better

     Understanding of Algorithmic Collusion



          Carlos Eduardo Veras Neves*& Tanise Brandao Bussmann**




Abstract. This paper introduces a Smart Agent-Based Modelling (SABM) within
computational antitrust framework to simulate and detect conditions fostering
algorithmic collusion. Using SABM, we document how  Large Language Model
(LLM)-driven agents achieve tacit collusion in a Bertrand duopoly, stabilizing prices
above competitive levels without being explicitly instructed to do so. Simulations in
English and Portuguese reveal that linguistic context influences outcomes, and
communication   between  agents potentializes emergent behaviors, such as
mimicking concerns about collusion. These findings highlight SABM's potential to
enhance regulatory oversight, offering an accessible tool for antitrust authorities to
help address autonomous algorithmic collusion of pricing agents in digital markets.


KEYWORDS:  Algorithmic collusion; Computational antitrust; Smart agent-based
modelling; Large Language Models; Tacit collusion; Bertrand duopoly


JEL: C63, C73, D43, K21, L13, 033



* PhD, Cerebro Project, CADE, Brasil, carlos.neves@cade.gov.br. The authors declare no conflict of
interest. This research received no institutional funding. Maritaca AI provided a limited number of API
credits to support the computational experiments; no financial compensation was involved.
* * PhD, Cerebro Project, CADE, Brasil