activity
20242026
collaborators

8 papers

cs.GT2026

Online Resource Allocation via Static Bundle Pricing

Dimitris Fotakis, Charalampos Platanos, Thanos Tolias

Online Resource Allocation addresses the problem of efficiently allocating limited resources to buyers with incomplete knowledge of future requests. In our setting, buyers arrive s…

cs.LG2025

GLANCE: Global Actions in a Nutshell for Counterfactual Explainability

Loukas Kavouras, Eleni Psaroudaki, Konstantinos Tsopelas +9

The widespread deployment of machine learning systems in critical real-world decision-making applications has highlighted the urgent need for counterfactual explainability methods…

cs.LG2025

Analyzing the Effect of Embedding Norms and Singular Values to Oversmoothing in Graph Neural Networks

Dimitrios Kelesis, Dimitris Fotakis, Georgios Paliouras

In this paper, we study the factors that contribute to the effect of oversmoothing in deep Graph Neural Networks (GNNs). Specifically, our analysis is based on a new metric (Mean A…

cs.GT2025

A Competitive Posted-Price Mechanism for Online Budget-Feasible Auctions

Andreas Charalampopoulos, Dimitris Fotakis, Panagiotis Patsilinakos +1

We consider online procurement auctions, where the agents arrive sequentially, in random order, and have private costs for their services. The buyer aims to maximize a monotone sub…

cs.DS2025

A Query-Driven Approach to Space-Efficient Range Searching

Dimitris Fotakis, Andreas Kalavas, Ioannis Psarros

We initiate a study of a query-driven approach to designing partition trees for range-searching problems. Our model assumes that a data structure is to be built for an unknown quer…

cs.DS2025

Polynomial Time Learning-Augmented Algorithms for NP-hard Permutation Problems

Evripidis Bampis, Bruno Escoffier, Dimitris Fotakis +2

We consider a learning-augmented framework for NP-hard permutation problems. The algorithm has access to predictions telling, given a pair of elements, whether is before…