Journal articles, conference papers, and working papers, most recent first.
My research sits at the intersection of AI, industrial organization, and competition policy — digital markets, market design, energy platforms, and AI regulation, studied with game theory, empirical methods, and machine learning.
2026
2026
arXiv
Shared Bidding Algorithms and Competition: Evidence from Electricity Markets
We introduce Multi-Agent Deep Hedging (MADH), a computational framework that extends deep reinforcement learning to markets with endogenous price formation. MADH embeds a differentiable market-clearing mechanism into the learning process, enabling decentralized agents to internalize their price impact via gradient ascent. We apply MADH to peer-to-peer electricity trading, benchmarking it against a centralized welfare-maximizing planner. Using synthetic data for heterogeneous prosumer communities, we demonstrate that decentralized agents autonomously learn sophisticated arbitrage strategies, such as capacity withholding. Crucially, we find that this strategic behavior generates positive externalities: while active traders reduce their own costs through price-awareness, their arbitrage smooths market prices, reducing costs for passive consumers. Furthermore, quantitative regret analysis confirms that MADH policies converge with low regret < 1.5%. These results establish MADH as a scalable tool for designing stable and efficient autonomous trading platforms.
@article{greber-eschenbaum-szehr-2026,author={Greber, Nicolas and Eschenbaum, Nicolas and Szehr, Oleg},journal={Energy and AI},title={Peer-to-Peer Electricity Platforms with Endogenous Prices: A Multi-Agent Neural Network Control Approach},year={2026},keywords={Peer-to-peer (P2P) electricity trading, Energy platforms, Multi-agent reinforcement learning, Neural networks, Market design},}
arXiv
Market Power and Platform Design in Decentralized Electricity Trading
@unpublished{eschenbaum-greber-marketpower-2026,author={Eschenbaum, Nicolas and Greber, Nicolas},title={Market Power and Platform Design in Decentralized Electricity Trading},month=mar,year={2026},keywords={Peer-to-peer electricity trading, Market power, Platform design, Market design},}
WC
Selective Confusion: An Empirical Analysis of the DMA’s Brussels Effect
Peter Georg Picht, Luka Nenadic, Octavia Barnes, and 2 more authors
This article examines the extent to which designated “gatekeepers” implement the provisions of the EU’s Digital Markets Act outside its territorial scope ("Brussels Effect"). Drawing on transparency reports, contractual documents, and informal communications, we reveal significant disparities in compliance strategies. Apple, Google, and Booking predominantly restrict their implementation to the EU or EEA, whereas Microsoft, Meta, and ByteDance extend certain measures to non-EU jurisdictions, notably Switzerland. Crucially, obligations subject to non-compliance proceedings by the European Commission are rarely extended beyond the EU, suggesting a strategic approach to territorial extensions of the DMA’s implementation. The article also uncovers a pattern of complex and sometimes contradictory communication by gatekeepers, raising questions about the transparency of the DMA’s implementation. These inconsistencies, coupled with selective extensions of specific data-related DMA provisions, point to a fragmented “Brussels Effect” of the law. The findings also imply that gatekeepers weigh the economic and strategic costs of compliance when deciding on territorial scope, and that the DMA’s global impact may depend on further coordination between regulators as well as more stringent enforcement.
@article{picht-etal-selective-confusion-2025,author={Picht, Peter Georg and Nenadic, Luka and Barnes, Octavia and Kuster, Yannick and Eschenbaum, Nicolas},journal={World Competition},title={Selective Confusion: An Empirical Analysis of the DMA's Brussels Effect},year={2026},note={Forthcoming},keywords={Digital Markets Act, gatekeepers, Brussels Effect, digital platforms, Apple, Google, enforcement, interoperability, compliance strategies, strategic ambiguity},}
2025
2025
SZW
DMA (Verw-)Irrungen: Was die territorialen Umsetzungsstrategien der Torwächter über den Digital Markets Act lehren
Peter Georg Picht, Luka Nenadic, Octavia Barnes, and 2 more authors
Schweizerische Zeitschrift für Wirtschafts- und Finanzmarktrecht (SZW), Mar 2025
@article{picht-etal-szw-2025,author={Picht, Peter Georg and Nenadic, Luka and Barnes, Octavia and Eschenbaum, Nicolas and Kuster, Yannick},journal={Schweizerische Zeitschrift für Wirtschafts- und Finanzmarktrecht (SZW)},title={DMA (Verw-)Irrungen: Was die territorialen Umsetzungsstrategien der Torwächter über den Digital Markets Act lehren},year={2025},number={4},keywords={Digital Markets Act, gatekeepers, Brussels Effect, territorial scope, enforcement},url={https://www.szw.ch/de/artikel/2504-0685-2025-0028/dma-verw-irrungen},}
arXiv
Dynamic Monopoly Pricing With Multiple Varieties: Trading Up
Stefan Buehler, Nicolas Eschenbaum, and Severin Lenhard
This paper develops an analytical framework that captures a broad class of monopoly pricing problems, aiming to explain why Coasian dynamics emerge in some settings while Coasian failures arise in others. We introduce the notion of trading-up opportunities and show that they are the driving force behind Coasian dynamics. In particular, pricing dynamics do not emerge in the absence of trading-up opportunities—a Coasian failure. Instead, with trading-up opportunities, pricing dynamics arise until these opportunities are exhausted or the game ends. We show how our analysis generalizes to transitional games where one variety is only indirectly accessible.
@unpublished{buehler-eschenbaum-lenhard-2025,author={Buehler, Stefan and Eschenbaum, Nicolas and Lenhard, Severin},title={Dynamic Monopoly Pricing With Multiple Varieties: Trading Up},month=dec,year={2025},}
WP
Dynamic Pricing in Bilateral Relationships: Experimental Evidence
Stefan Buehler, Thomas Epper, Nicolas Eschenbaum, and 1 more author
This paper presents experimental evidence on dynamic pricing in a large number of finite-horizon bilateral relationships, building on Hart and Tirole (1988). We examine four distinct treatments that vary the mode of trade and the seller’s commitment ability. We find that theory accurately predicts average prices across relationships but falls short of capturing the diversity of individual price trajectories. We also find that commitment has less bite than theory predicts, with sellers leaving significant rents to buyers and frequently committing to changing or oscillating prices. Our analysis suggests that theory explains behavior under renting better than under selling.
@unpublished{dynamic-pricing-experiment-2025,author={Buehler, Stefan and Epper, Thomas and Eschenbaum, Nicolas and Koch, Roberta},title={Dynamic Pricing in Bilateral Relationships: Experimental Evidence},month=dec,year={2025},}
arXiv
Repeated Auctions with Speculators: Arbitrage Incentives and Forks in DAOs
We analyze the vulnerability of decentralized autonomous organizations (DAOs) to speculative exploitation via their redemption mechanisms. Studying a game-theoretic model of repeated auctions for governance shares with speculators, we characterize the conditions under which—in equilibrium—an exploitative exit is guaranteed to occur, occurs in expectation, or never occurs. We evaluate four redemption mechanisms and extend our model to include atomic exits, time delays, and DAO spending strategies. Our results highlight an inherent tension in DAO design: mechanisms intended to protect members from majority attacks can inadvertently create opportunities for costly speculative exploitation. We highlight governance mechanisms that can be used to prevent speculation.
@unpublished{eschenbaum-greber-daos-2025,author={Eschenbaum, Nicolas and Greber, Nicolas},title={Repeated Auctions with Speculators: Arbitrage Incentives and Forks in DAOs},month=may,year={2025},}
2024
2024
sic!
Schweizer DMA-Brussels-Effect? Wie Gatekeeper den DMA in der Schweiz (nicht) umsetzen
Peter Georg Picht, Luka Nenadic, Octavia Barnes, and 2 more authors
sic! Zeitschrift für Immaterialgüter-, Informations- und Wettbewerbsrecht, May 2024
@article{picht-etal-sic-2024,author={Picht, Peter Georg and Nenadic, Luka and Barnes, Octavia and Eschenbaum, Nicolas and Kuster, Yannick},journal={sic! Zeitschrift für Immaterialgüter-, Informations- und Wettbewerbsrecht},title={Schweizer DMA-Brussels-Effect? Wie Gatekeeper den DMA in der Schweiz (nicht) umsetzen},year={2024},pages={3 - 14},keywords={Digital Markets Act, gatekeepers, Brussels Effect, Switzerland, platform regulation},url={https://www.zora.uzh.ch/entities/publication/763e6f62-f9a4-440e-9187-11f3ba77cac7},}
2022
2022
arXiv
Robust Algorithmic Collusion
Nicolas Eschenbaum, Filip Mellgren, and Philipp Zahn
This paper develops a formal framework to assess policies of learning algorithms in economic games. We investigate whether reinforcement-learning agents with collusive pricing policies can successfully extrapolate collusive behavior from training to the market. We find that in testing environments collusion consistently breaks down. Instead, we observe static Nash play. We then show that restricting algorithms’ strategy space can make algorithmic collusion robust, because it limits overfitting to rival strategies. Our findings suggest that policy-makers should focus on firm behavior aimed at coordinating algorithm design in order to make collusive policies robust.
@unpublished{eschenbaum-mellgren-zahn-2022,author={Eschenbaum, Nicolas and Mellgren, Filip and Zahn, Philipp},title={Robust Algorithmic Collusion},year={2022},note={Presented at the NeurIPS PERLS workshop},}
2021
2021
arXiv
Dealing with Uncertainty: The Value of Reputation in the Absence of Legal Institutions
This paper studies reputation in the online market for illegal drugs in which no legal institutions exist to alleviate uncertainty. Trade takes place on platforms that offer rating systems for sellers, thereby providing an observable measure of reputation. The analysis exploits the fact that one of the two dominant platforms unexpectedly disappeared. Re-entering sellers reset their rating. The results show that on average prices decreased by up to 9% and that a 1% increase in rating causes a price increase of 1%. Ratings and prices recover after about three months. We calculate that identified good types earn 1,650 USD more per week.
@unpublished{eschenbaum-liebert-2021,author={Eschenbaum, Nicolas and Liebert, Helge},title={Dealing with Uncertainty: The Value of Reputation in the Absence of Legal Institutions},month=may,year={2021},keywords={Reputation, institutions, uncertainty, dark web, drugs},}
2020
2020
JEBO
Explaining escalating prices and fines: A unified approach
Stefan Buehler, and Nicolas Eschenbaum
Journal of Economic Behavior & Organization, May 2020
This paper provides an explanation for escalating prices and fines based on a unified analytical framework that nests monopoly pricing and optimal law enforcement. We show that escalation emerges as an optimal outcome if the principal (i) lacks commitment ability, and (ii) gives less than full weight to agent benefits. Escalation is driven by decreasing transfers for non-active agents rather than increasing transfers for active agents. Some forward-looking agents then strategically delay their activity, which drives a wedge between the optimal static transfer and the benefit of an indifferent agent. This wedge is the source of escalation.
@article{buehler-eschenbaum-2020,author={Buehler, Stefan and Eschenbaum, Nicolas},journal={Journal of Economic Behavior & Organization},title={Explaining escalating prices and fines: A unified approach},year={2020},issn={0167-2681},pages={153 - 164},volume={171},doi={https://doi.org/10.1016/j.jebo.2020.01.008},keywords={Escalation, Behavior-based pricing, Repeat offenders, Deterrence},url={http://www.sciencedirect.com/science/article/pii/S0167268120300093},}
2018
2018
WP
Estimating Geographic Market Size Nonparametrically: An Application to Grocery Retailing
This paper develops a nonparametric approach to empirically determine geographic market size. I exploit highly detailed spatial data and provide estimates of business-stealing effects across distance by studying the impact of store entry on competitors in an increasing range to the entry site. Entropy balancing is employed to control for systematic differences across local markets. I estimate that markets for Swiss grocery retailing stores are highly localized in a tight four kilometer radius. I further document evidence that the impact weakens with increasing distance and that smaller retailers compete in a more narrow market of only two kilometers in size.