167 citations · 210 across the 72 of their papers we have counts for
23 papers · 1 filter
Through the PRISm: Importance-Aware Scene Graphs for Semantic Image Retrieval
Dimitrios Georgoulopoulos, Nikolaos Chaidos, Angeliki Dimitriou +1
Web-based visual search increasingly handles queries driven by semantic intent, focusing on what is happening in an image rather than merely what it looks like. While global embedd…
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…
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…
ATLAS: Adaptive Trading with LLM AgentS Through Dynamic Prompt Optimization and Multi-Agent Coordination
Charidimos Papadakis, Angeliki Dimitriou, Giorgos Filandrianos +3
Large language models show promise for financial decision-making, yet deploying them as autonomous trading agents raises fundamental challenges: how to adapt instructions when rewa…
Go witheFlow: Real-time Emotion Driven Audio Effects Modulation
Edmund Dervakos, Spyridon Kantarelis, Vassilis Lyberatos +2
Music performance is a distinctly human activity, intrinsically linked to the performer's ability to convey, evoke, or express emotion. Machines cannot perform music in the human s…
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…
Exploring How Audio Effects Alter Emotion with Foundation Models
Stelios Katsis, Vassilis Lyberatos, Spyridon Kantarelis +2
Audio effects (FX) such as reverberation, distortion, modulation, and dynamic range processing play a pivotal role in shaping emotional responses during music listening. While prio…
StockSim: A Dual-Mode Order-Level Simulator for Evaluating Multi-Agent LLMs in Financial Markets
Charidimos Papadakis, Giorgos Filandrianos, Angeliki Dimitriou +3
We present StockSim, an open-source simulation platform for systematic evaluation of large language models (LLMs) in realistic financial decision-making scenarios. Unlike previous…
Enhancing Cooperative Multi-Agent Reinforcement Learning with State Modelling and Adversarial Exploration
Andreas Kontogiannis, Konstantinos Papathanasiou, Yi Shen +3
Learning to cooperate in distributed partially observable environments with no communication abilities poses significant challenges for multi-agent deep reinforcement learning (MAR…
Music Interpretation and Emotion Perception: A Computational and Neurophysiological Investigation
Vassilis Lyberatos, Spyridon Kantarelis, Ioanna Zioga +3
This study investigates emotional expression and perception in music performance using computational and neurophysiological methods. The influence of different performance settings…
PAKTON: A Multi-Agent Framework for Question Answering in Long Legal Agreements
Petros Raptopoulos, Giorgos Filandrianos, Maria Lymperaiou +1
Contract review is a complex and time-intensive task that typically demands specialized legal expertise, rendering it largely inaccessible to non-experts. Moreover, legal interpret…
Don't Erase, Inform! Detecting and Contextualizing Harmful Language in Cultural Heritage Collections
Orfeas Menis Mastromichalakis, Jason Liartis, Kristina Rose +2
Cultural Heritage (CH) data hold invaluable knowledge, reflecting the history, traditions, and identities of societies, and shaping our understanding of the past and present. Howev…
SCENIR: Visual Semantic Clarity through Unsupervised Scene Graph Retrieval
Nikolaos Chaidos, Angeliki Dimitriou, Maria Lymperaiou +1
Despite the dominance of convolutional and transformer-based architectures in image-to-image retrieval, these models are prone to biases arising from low-level visual features, suc…
Semantic-Aware Interpretable Multimodal Music Auto-Tagging
Andreas Patakis, Vassilis Lyberatos, Spyridon Kantarelis +2
Music auto-tagging is essential for organizing and discovering music in extensive digital libraries. While foundation models achieve exceptional performance in this domain, their o…
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…
Assumed Identities: Quantifying Gender Bias in Machine Translation of Gender-Ambiguous Occupational Terms
Orfeas Menis Mastromichalakis, Giorgos Filandrianos, Maria Symeonaki +1
Machine Translation (MT) systems frequently encounter gender-ambiguous occupational terms, where they must assign gender without explicit contextual cues. While individual translat…
Conceptual Contrastive Edits in Textual and Vision-Language Retrieval
Maria Lymperaiou, Giorgos Stamou
As deep learning models grow in complexity, achieving model-agnostic interpretability becomes increasingly vital. In this work, we employ post-hoc conceptual contrastive edits to e…
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…
Pitfalls of Scale: Investigating the Inverse Task of Redefinition in Large Language Models
Elena Stringli, Maria Lymperaiou, Giorgos Filandrianos +2
Inverse tasks can uncover potential reasoning gaps as Large Language Models (LLMs) scale up. In this work, we explore the redefinition task, in which we assign alternative values t…
Bias Beware: The Impact of Cognitive Biases on LLM-Driven Product Recommendations
Giorgos Filandrianos, Angeliki Dimitriou, Maria Lymperaiou +2
The advent of Large Language Models (LLMs) has revolutionized product recommenders, yet their susceptibility to adversarial manipulation poses critical challenges, particularly in…