51 citations · 242 across the 22 of their papers we have counts for
13 papers · 1 filter
Optimality Despite Chaos in Fee Markets
Stefanos Leonardos, Daniël Reijsbergen, Barnabé Monnot +1
Transaction fee markets are essential components of blockchain economies, as they resolve the inherent scarcity in the number of transactions that can be added to each block. In ea…
Transaction Fees on a Honeymoon: Ethereum's EIP-1559 One Month Later
Daniël Reijsbergen, Shyam Sridhar, Barnabé Monnot +3
Ethereum Improvement Proposal (EIP) 1559 was recently implemented to transform Ethereum's transaction fee market. EIP-1559 utilizes an algorithmic update rule with a constant learn…
Exploration-Exploitation in Multi-Agent Competition: Convergence with Bounded Rationality
Stefanos Leonardos, Georgios Piliouras, Kelly Spendlove
The interplay between exploration and exploitation in competitive multi-agent learning is still far from being well understood. Motivated by this, we study smooth Q-learning, a pro…
From Griefing to Stability in Blockchain Mining Economies
Yun Kuen Cheung, Stefanos Leonardos, Georgios Piliouras +1
We study a game-theoretic model of blockchain mining economies and show that griefing, a practice according to which participants harm other participants at some lesser cost to the…
Learning in Markets: Greed Leads to Chaos but Following the Price is Right
Yun Kuen Cheung, Stefanos Leonardos, Georgios Piliouras
We study learning dynamics in distributed production economies such as blockchain mining, peer-to-peer file sharing and crowdsourcing. These economies can be modelled as multi-prod…
Dynamical Analysis of the EIP-1559 Ethereum Fee Market
Stefanos Leonardos, Barnabé Monnot, Daniël Reijsbergen +2
Participation in permissionless blockchains results in competition over system resources, which needs to be controlled with fees. Ethereum's current fee mechanism is implemented vi…
Exploration-Exploitation in Multi-Agent Learning: Catastrophe Theory Meets Game Theory
Stefanos Leonardos, Georgios Piliouras
Exploration-exploitation is a powerful and practical tool in multi-agent learning (MAL), however, its effects are far from understood. To make progress in this direction, we study…
Catastrophe by Design in Population Games: Destabilizing Wasteful Locked-in Technologies
Stefanos Leonardos, Iosif Sakos, Costas Courcoubetis +1
In multi-agent environments in which coordination is desirable, the history of play often causes lock-in at sub-optimal outcomes. Notoriously, technologies with a significant envir…
Oceanic Games: Centralization Risks and Incentives in Blockchain Mining
Nikos Leonardos, Stefanos Leonardos, Georgios Piliouras
To participate in the distributed consensus of permissionless blockchains, prospective nodes -- or miners -- provide proof of designated, costly resources. However, in contrast to…
Weighted Voting on the Blockchain: Improving Consensus in Proof of Stake Protocols
Stefanos Leonardos, Daniel Reijsbergen, Georgios Piliouras
Proof of Stake (PoS) protocols rely on voting mechanisms to reach consensus on the current state. If an enhanced majority of staking nodes, also called validators, agree on a propo…
Measuring Market Performance with Stochastic Demand: Price of Anarchy and Price of Uncertainty
Costis Melolidakis, Stefanos Leonardos, Constandina Koki
Globally operating suppliers face the rising challenge of wholesale pricing under scarce data about retail demand, in contrast to better informed, locally operating retailers. At t…
Comparative Statics via Stochastic Orderings in a Two-Echelon Market with Upstream Demand Uncertainty
Constandina Koki, Stefanos Leonardos, Costis Melolidakis
We revisit the classic Cournot model and extend it to a two-echelon supply chain with an upstream supplier who operates under demand uncertainty and multiple downstream retailers w…
On the commitment value and commitment optimal strategies in bimatrix games
Stefanos Leonardos, Costis Melolidakis
Given a bimatrix game, the associated leadership or commitment games are defined as the games at which one player, the leader, commits to a (possibly mixed) strategy and the other…