activity
20122026
most citedClustering and Community Detection in Directed Networks: A Survey

599 citations · 1.2k across the 114 of their papers we have counts for

collaborators

135 papers

cs.LG2026

Latent Flow Matching for Molecular Graph Generation

Mathis Goupillon, Roman Bresson, Konstantinos Divriotis +1

Modern graph generative models typically operate directly in the discrete graph space, explicitly generating node and edge variables, which can become costly as graphs grow. In thi…

cs.LG2026

Refining Heuristic-Based Bitcoin Address Clustering with Graph Neural Networks

Hugo Schnoering, Roman Bresson, Michalis Vazirgiannis

Bitcoin's pseudonymous nature makes it challenging to analyze user-level activity, since a single user may control multiple identifiers (addresses). Existing heuristic-based method…

cs.CL2026

Every Wrong Answer Counts: Option-Level Psychometrics for LLM Multiple-Choice Benchmarks

Xiao Fei, Yang Zhang, Sarah Almeida Carneiro +1

Most multiple-choice question (MCQ) benchmarks evaluate Large Language Models (LLMs) only by whether they select the correct answers. This binary scoring treats all incorrect respo…

cs.CL2026

Jais 2: A Family of Arabic-Centric Open Large Language Models

Mohamed Anwar, Abed Alhakim Freihat, George Ibrahim +57

Jais 2 is a family of Arabic-centric large language models developed jointly by MBZUAI, Cerebras, and Inception, designed to advance Arabic-centric language modeling, with strong p…

cs.CL2026

The Masked Advantage: Uncovering Local-Language Access to Cultural Knowledge in LLMs

Yang Zhang, Xiao Fei, Amr Mohamed +6

Large language models are increasingly used to answer culturally grounded questions across languages, yet it remains unclear whether local cultural knowledge is better accessed thr…

cs.CL2026

CARTE: A Benchmark for Mapping Language Model Knowledge Across France

Sarah Almeida Carneiro, Christos Xypolopoulos, Xiao Fei +2

We introduce CARTE (Culturally Anchored Regional-Territorial Evaluation), a multiple-choice benchmark for evaluating the ability of large language models (LLMs) to discriminate fin…

cs.LG2026

GraViti: Graph-Level Variational Autoencoders with Relaxed Permutation Invariance

Roman Bresson, Konstantinos Divriotis, Johannes F. Lutzeyer +2

We introduce GraViti, a transformer-based graph-level variational autoencoder that encodes entire graphs into single, fixed-dimensional latent vectors rather than per-node embeddin…

cs.CE2026

PPI2Text: Captioning Protein-Protein Interactions with Coordinate-Aligned Pair-Map Decoding

Xiao Fei, Sarah Almeida Carneiro, Yang Zhang +4

Protein-protein interaction (PPI) modeling has been widely studied as a binary or multi-label classification task. While emerging multimodal large language models (LLMs) can now de…

cs.CL2026

GreekMMLU: A Native-Sourced Multitask Benchmark for Evaluating Language Models in Greek

Yang Zhang, Mersin Konomi, Christos Xypolopoulos +6

Large Language Models (LLMs) are commonly trained on multilingual corpora that include Greek, yet reliable evaluation benchmarks for Greek-particularly those based on authentic, na…

cs.CL2026

Markovian Generation Chains in Large Language Models

Mingmeng Geng, Amr Mohamed, Guokan Shang +2

The widespread use of large language models (LLMs) raises an important question: how do texts evolve when they are repeatedly processed by LLMs? In this paper, we define this itera…

cs.LG2026

A Kinetic Energy Perspective of Flow Matching

Ziyun Li, Huancheng Hu, Soon Hoe Lim +6

Flow-based generative models can be viewed through a physics lens: sampling transports a particle from noise to data by integrating a learned velocity field, and each sample corres…

cs.AI2026

YaPO: Learnable Sparse Activation Steering Vectors for Domain Adaptation

Abdelaziz Bounhar, Rania Hossam Elmohamady Elbadry, Hadi Abdine +3

Steering Large Language Models (LLMs) through activation interventions has emerged as a lightweight alternative to fine-tuning for alignment and personalization. Recent work on Bi-…

cs.CL2025

A Greek Government Decisions Dataset for Public-Sector Analysis and Insight

Giorgos Antoniou, Giorgos Filandrianos, Aggelos Vlachos +4

We introduce an open, machine-readable corpus of Greek government decisions sourced from the national transparency platform Diavgeia. The resource comprises 1 million decisions, fe…

cs.CL2025

Fast-Decoding Diffusion Language Models via Progress-Aware Confidence Schedules

Amr Mohamed, Yang Zhang, Michalis Vazirgiannis +1

Diffusion large language models (dLLMs) offer a promising alternative to autoregressive models, but their practical utility is severely hampered by slow, iterative sampling. We pre…

cs.LG2025

Shorter but not Worse: Frugal Reasoning via Easy Samples as Length Regularizers in Math RLVR

Abdelaziz Bounhar, Hadi Abdine, Evan Dufraisse +5

Large language models (LLMs) trained for step-by-step reasoning often become excessively verbose, raising inference cost. Standard Reinforcement Learning with Verifiable Rewards (R…

cs.LG2025

If You Want to Be Robust, Be Wary of Initialization

Sofiane Ennadir, Johannes F. Lutzeyer, Michalis Vazirgiannis +1

Graph Neural Networks (GNNs) have demonstrated remarkable performance across a spectrum of graph-related tasks, however concerns persist regarding their vulnerability to adversaria…

cs.LG2025

Cell2Text: Multimodal LLM for Generating Single-Cell Descriptions from RNA-Seq Data

Oussama Kharouiche, Aris Markogiannakis, Xiao Fei +2

Single-cell RNA sequencing has transformed biology by enabling the measurement of gene expression at cellular resolution, providing information for cell types, states, and disease…

cs.LG2025

ADMP-GNN: Adaptive Depth Message Passing GNN

Yassine Abbahaddou, Fragkiskos D. Malliaros, Johannes F. Lutzeyer +1

Graph Neural Networks (GNNs) have proven to be highly effective in various graph learning tasks. A key characteristic of GNNs is their use of a fixed number of message-passing step…

cs.CL2025

Nile-Chat: Egyptian Language Models for Arabic and Latin Scripts

Guokan Shang, Hadi Abdine, Ahmad Chamma +7

We introduce Nile-Chat-4B, 3x4B-A6B, and 12B, a collection of LLMs for Egyptian dialect, uniquely designed to understand and generate texts written in both Arabic and Latin scripts…

cs.CL2025

Lost in the Mix: Evaluating LLM Understanding of Code-Switched Text

Amr Mohamed, Yang Zhang, Michalis Vazirgiannis +1

Code-switching (CSW) is the act of alternating between two or more languages within a single discourse. This phenomenon is widespread in multilingual communities, and increasingly…

cs.CL2025★ 1 cited

Beyond Random Sampling: Efficient Language Model Pretraining via Curriculum Learning

Yang Zhang, Amr Mohamed, Hadi Abdine +2

Curriculum learning-organizing training data from easy to hard-has improved efficiency across machine learning domains, yet remains underexplored for language model pretraining. We…

cs.CE2025

Prot2Text-V2: Protein Function Prediction with Multimodal Contrastive Alignment

Xiao Fei, Michail Chatzianastasis, Sarah Almeida Carneiro +3

Predicting protein function from sequence is a central challenge in computational biology. While existing methods rely heavily on structured ontologies or similarity-based techniqu…

cs.LG2025

Prediction via Shapley Value Regression

Amr Alkhatib, Roman Bresson, Henrik Boström +1

Shapley values have several desirable, theoretically well-supported, properties for explaining black-box model predictions. Traditionally, Shapley values are computed post-hoc, lea…

cs.IR2025★ 3 cited

Rolling Forward: Enhancing LightGCN with Causal Graph Convolution for Credit Bond Recommendation

Ashraf Ghiye, Baptiste Barreau, Laurent Carlier +1

Graph Neural Networks have significantly advanced research in recommender systems over the past few years. These methods typically capture global interests using aggregated past in…