collaborators

10 papers

cs.GT2026

Approximate Envy-Free Allocations up to any Goods

Aris Filos-Ratsikas, Georgios Kalantzis, Fangxiao Wang

We study the problem of finding approximate envy-free allocations up to any goods (-EFkX), when agents have additive values over goods in a bundle. As our main result, we s…

cs.GT2026

Efficient Equilibrium Computation in Symmetric First-Price Auctions

Aris Filos-Ratsikas, Yiannis Giannakopoulos, Alexandros Hollender +1

We study the complexity of computing Bayes-Nash equilibria in single-item first-price auctions. We present the first efficient algorithms for the problem, when the bidders' values…

cs.GT2026

Proportionality Degree in Participatory Budgeting

Aris Filos-Ratsikas, Sreedurga Gogulapati, Georgios Kalantzis

We initiate the study of the proportionality degree for participatory budgeting, with a particular focus on two popular methods: the Method of Equal Shares (MES) and Phragmen's Seq…

cs.GT2026

A Theoretical Approach to Stablecoin Design via Price Windows

Katherine Molinet, Aris Filos-Ratsikas

In this paper, we explore the short- and long-term stability of backed stablecoins offering constant mint and redeem prices to all agents. We refer to such designs as price window-…

cs.GT2026

The Distortion of Stable Matching

Aris Filos-Ratsikas, Georgios Kalantzis

We initiate the study of distortion in stable matching. Concretely, we aim to design algorithms that have limited access to the agents' cardinal preferences and compute stable matc…

cs.GT2026

Approximate-EFX Allocations with Ordinal and Limited Cardinal Information

Aris Filos-Ratsikas, Georgios Kalantzis, Alexandros A. Voudouris

We study a discrete fair division problem where agents have additive valuation functions over a set of goods. We focus on the well-known -EFX fairness criterion, accord…