18 papers
Towards AI-Generated Music Plagiarism Detection as a Version Identification Problem
Fotis Koutsikos, Ioannis Prokopiou, Spyridon Kantarelis +6
The rapid expansion of text-to-music generative models challenges traditional paradigms of music creation and intellectual property. Plagiarism in this context is rarely an absolut…
Multimodal Sexism Identification and Characterization using Large Language Models and Gradient Boosting
Kyriakos Chaviaras, Maria Lymperaiou, Athanasios Voulodimos
We present the AILS-NTUA submission to the EXIST 2026 Lab at CLEF, addressing multimodal sexism identification and characterization in memes (Task 2) and short-form videos (Task 3)…
Exploration of Perceptual Speech Features for Clinical Decision-Support in Mental Health Care
Vassilis Lyberatos, Edmund G. Dervakos, Eleni Adamidi +2
Speech and language technologies offer valuable opportunities for supporting mental health assessment through objective and interpretable cues. We present a systematic feature-base…
Optimal Recourse Summaries via Bi-Objective Decision Tree Learning
Ioannis Chatzis, Jason Liartis, Athanasios Voulodimos +1
Actionable Recourse provides individuals with actions they can take to change an unfavorable classifier outcome. While useful at the instance level, it is ill-suited for global aud…
AILS-NTUA at SemEval-2026 Task 8: Evaluating Multi-Turn RAG Conversations
Dimosthenis Athanasiou, Maria Lymperaiou, Giorgos Filandrianos +2
We present the AILS-NTUA system for SemEval-2026 Task 8 (MTRAGEval), addressing all three subtasks of multi-turn retrieval-augmented generation: passage retrieval (A), reference-gr…
AILS-NTUA at SemEval-2026 Task 3: Efficient Dimensional Aspect-Based Sentiment Analysis
Stavros Gazetas, Giorgos Filandrianos, Maria Lymperaiou +3
In this paper, we present AILS-NTUA system for Track-A of SemEval-2026 Task 3 on Dimensional Aspect-Based Sentiment Analysis (DimABSA), which encompasses three complementary proble…
AILS-NTUA at SemEval-2026 Task 10: Agentic LLMs for Psycholinguistic Marker Extraction and Conspiracy Endorsement Detection
Panagiotis Alexios Spanakis, Maria Lymperaiou, Giorgos Filandrianos +2
This paper presents a novel agentic LLM pipeline for SemEval-2026 Task 10 that jointly extracts psycholinguistic conspiracy markers and detects conspiracy endorsement. Unlike tradi…
AILS-NTUA at SemEval-2026 Task 12: Graph-Based Retrieval and Reflective Prompting for Abductive Event Reasoning
Nikolas Karafyllis, Maria Lymperaiou, Giorgos Filandrianos +2
We present a winning three-stage system for SemEval 2026 Task~12: Abductive Event Reasoning that combines graph-based retrieval, LLM-driven abductive reasoning with prompt design o…
CSE-UOI at SemEval-2026 Task 6: A Two-Stage Heterogeneous Ensemble with Deliberative Complexity Gating for Political Evasion Detection
Christos Tzouvaras, Konstantinos Skianis, Athanasios Voulodimos
This paper describes our system for SemEval-2026 Task 6, which classifies clarity of responses in political interviews into three categories: Clear Reply, Ambivalent, and Clear Non…
Reasoning or Pattern Matching? Probing Large Vision-Language Models with Visual Puzzles
Maria Lymperaiou, Vasileios Karampinis, Giorgos Filandrianos +3
Puzzles have long served as compact and revealing probes of human cognition, isolating abstraction, rule discovery, and systematic reasoning with minimal reliance on prior knowledg…
Sparse Computations in Deep Learning Inference
Ioanna Tasou, Panagiotis Mpakos, Angelos Vlachos +25
The computational demands of modern Deep Neural Networks (DNNs) are immense and constantly growing. While training costs usually capture public attention, inference demands are als…
V-CECE: Visual Counterfactual Explanations via Conceptual Edits
Nikolaos Spanos, Maria Lymperaiou, Giorgos Filandrianos +3
Recent black-box counterfactual generation frameworks fail to take into account the semantic content of the proposed edits, while relying heavily on training to guide the generatio…
Analyze-Prompt-Reason: A Collaborative Agent-Based Framework for Multi-Image Vision-Language Reasoning
Angelos Vlachos, Giorgos Filandrianos, Maria Lymperaiou +4
We present a Collaborative Agent-Based Framework for Multi-Image Reasoning. Our approach tackles the challenge of interleaved multimodal reasoning across diverse datasets and task…
Explaining Vision GNNs: A Semantic and Visual Analysis of Graph-based Image Classification
Nikolaos Chaidos, Angeliki Dimitriou, Nikolaos Spanos +2
Graph Neural Networks (GNNs) have emerged as an efficient alternative to convolutional approaches for vision tasks such as image classification, leveraging patch-based representati…
AILS-NTUA at SemEval-2025 Task 8: Language-to-Code prompting and Error Fixing for Tabular Question Answering
Andreas Evangelatos, Giorgos Filandrianos, Maria Lymperaiou +2
In this paper, we present our submission to SemEval-2025 Task 8: Question Answering over Tabular Data. This task, evaluated on the DataBench dataset, assesses Large Language Models…
AILS-NTUA at SemEval-2025 Task 4: Parameter-Efficient Unlearning for Large Language Models using Data Chunking
Iraklis Premptis, Maria Lymperaiou, Giorgos Filandrianos +3
The Unlearning Sensitive Content from Large Language Models task aims to remove targeted datapoints from trained models while minimally affecting their general knowledge. In our wo…
AILS-NTUA at SemEval-2025 Task 3: Leveraging Large Language Models and Translation Strategies for Multilingual Hallucination Detection
Dimitra Karkani, Maria Lymperaiou, Giorgos Filandrianos +3
Multilingual hallucination detection stands as an underexplored challenge, which the Mu-SHROOM shared task seeks to address. In this work, we propose an efficient, training-free LL…
HalCECE: A Framework for Explainable Hallucination Detection through Conceptual Counterfactuals in Image Captioning
Maria Lymperaiou, Giorgos Filandrianos, Angeliki Dimitriou +2
In the dynamic landscape of artificial intelligence, the exploration of hallucinations within vision-language (VL) models emerges as a critical frontier. This work delves into the…