Demo Data from SIGIR 2026 / reviewers in the wild / expert
Maria Lymperaiou
dblp:329/4552
· DBLP profile ↗
10ranked-venue papers
1as first author
10since 2021 · last 2025
0000-0001-9442-4186ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 9 · 1 first-author · 9 since 2021Graphics, computer vision, multimedia, augmented reality and games · 1 · 1 since 2021
Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.
| Artificial intelligence
8 papers |
Trustworthy machine learning · 37% Graph learning · 14% Generative modeling · 12% | |
| Databases, data mining, and information retrieval
3 papers |
Information retrieval · 77% Recommender systems · 23% | |
| Computer graphics and multimedia
1 paper |
Multimedia analysis and retrieval · 100% |
Topics — the 23 heaviest of 26, each with the papers that count most for it
| Topic | Weight | Papers | Last | Evidence papers |
|---|---|---|---|---|
Machine learning › Trustworthy machine learning › interpretability
counterfactual explanation |
1.6 | 2 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 Structure Your Data: Towards Semantic Graph Counterfactuals · ICML 2024 |
Machine learning › Trustworthy machine learning
interpretability |
1.6 | 2 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 Structure Your Data: Towards Semantic Graph Counterfactuals · ICML 2024 |
Machine learning › Generative modeling
diffusion model |
0.9 | 1 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 |
Machine learning › Graph learning
graph autoencoder |
0.9 | 1 | 2025 | SCENIR: Visual Semantic Clarity through Unsupervised Scene Graph Retrieval · ICML 2025 |
Machine learning › Generative modeling › diffusion model
image editing |
0.9 | 1 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 |
Natural language and speech › Question answering and dialogue systems › domain-specific question answering
legal question answering |
0.9 | 1 | 2025 | PAKTON: A Multi-Agent Framework for Question Answering in Long Legal Agreements · EMNLP 2025 |
Computer vision › Vision and language
multimodal reasoning |
0.9 | 1 | 2025 | Analyze-Prompt-Reason: A Collaborative Agent-Based Framework for Multi-Image Vision-Language Reasoning · ACM Multimedia 2025 |
Machine learning › Graph learning › graph representation learning
unsupervised graph representation learning |
0.9 | 1 | 2025 | SCENIR: Visual Semantic Clarity through Unsupervised Scene Graph Retrieval · ICML 2025 |
Machine learning › Trustworthy machine learning › interpretability › counterfactual explanation
visual counterfactual explanation |
0.9 | 1 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 |
Information retrieval
retrieval-augmented generation |
0.9 | 1 | 2025 | PAKTON: A Multi-Agent Framework for Question Answering in Long Legal Agreements · EMNLP 2025 |
Multimedia analysis and retrieval
image retrieval |
0.9 | 1 | 2025 | SCENIR: Visual Semantic Clarity through Unsupervised Scene Graph Retrieval · ICML 2025 |
Machine learning › Trustworthy machine learning › interpretability
concept-based explanation |
0.8 | 1 | 2024 | Structure Your Data: Towards Semantic Graph Counterfactuals · ICML 2024 |
Natural language and speech › Language models and text generation
large language model reasoning |
0.8 | 1 | 2024 | Puzzle Solving using Reasoning of Large Language Models: A Survey · EMNLP 2024 |
Knowledge, reasoning and agents › Knowledge representation and reasoning
logic-based reasoning |
0.8 | 1 | 2024 | Puzzle Solving using Reasoning of Large Language Models: A Survey · EMNLP 2024 |
Knowledge, reasoning and agents › Planning, search and constraint satisfaction
puzzle solving |
0.8 | 1 | 2024 | Puzzle Solving using Reasoning of Large Language Models: A Survey · EMNLP 2024 |
Information retrieval › ranking
learning to rank |
0.7 | 1 | 2023 | Large Language Models and Multimodal Retrieval for Visual Word Sense Disambiguation · EMNLP 2023 |
Information retrieval
multimodal retrieval |
0.7 | 1 | 2023 | Large Language Models and Multimodal Retrieval for Visual Word Sense Disambiguation · EMNLP 2023 |
Information retrieval › ranking
rank aggregation |
0.7 | 1 | 2023 | Large Language Models and Multimodal Retrieval for Visual Word Sense Disambiguation · EMNLP 2023 |
Computer vision › Image recognition and object detection
image classification |
0.3 | 1 | 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual Edits · NeurIPS 2025 |
Computer vision › Vision and language › vision-language model
multimodal large language model |
0.3 | 1 | 2025 | Analyze-Prompt-Reason: A Collaborative Agent-Based Framework for Multi-Image Vision-Language Reasoning · ACM Multimedia 2025 |
Machine learning › Trustworthy machine learning
robustness |
0.3 | 1 | 2025 | Bias Beware: The Impact of Cognitive Biases on LLM-Driven Product Recommendations · EMNLP 2025 |
Machine learning › Graph learning
graph neural network |
0.2 | 1 | 2024 | Structure Your Data: Towards Semantic Graph Counterfactuals · ICML 2024 |
Computer vision › Vision and language
image-text retrieval |
0.2 | 1 | 2023 | Large Language Models and Multimodal Retrieval for Visual Word Sense Disambiguation · EMNLP 2023 |
Methods — techniques the papers use, named apart from their topics
graph neural network · 2.5graph edit distance · 2.5retrieval-augmented generation · 1.7multi-agent framework · 1.7cognitive biases · 1.7black-box adversarial strategies · 1.7vision transformer · 0.9large vision-language model · 0.9diffusion model · 0.9agent-based framework · 0.9transformer-based retrieval · 0.7learn-to-rank · 0.7chain-of-thought prompting · 0.7
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | RISCORE: Enhancing In-Context Riddle Solving in Language Models through Context-Reconstructed Example AugmentationabstractRiddle-solving requires advanced reasoning skills, pushing Large Language Models (LLMs) to engage in abstract thinking and creative problem-solving, often revealing limitations in their cognitive abilities. In this paper, we examine the riddle-solving capabilities of LLMs using a multiple-choice format, exploring how different prompting techniques impact performance on riddles that demand diverse reasoning skills. To enhance results, we introduce RISCORE (RIddle Solving with COntext REcontruciton) a novel fully automated prompting method that generates and utilizes contextually reconstructed sentence-based puzzles in conjunction with the original examples to create few-shot exemplars. Our experiments demonstrate that RISCORE significantly improves the performance of language models in both vertical and lateral thinking tasks, surpassing traditional exemplar selection strategies across a variety of few-shot settings. Ioannis Panagiotopoulos, Giorgos Filandrianos, Maria Lymperaiou, Giorgos B. Stamou |
COLING | 3 |
| 2025 | Bias Beware: The Impact of Cognitive Biases on LLM-Driven Product RecommendationsabstractThe advent of Large Language Models (LLMs) has revolutionized product recommenders, yet their susceptibility to adversarial manipulation poses critical challenges, particularly in realworld commercial applications.Our approach is the first one to tap into human psychological principles, seamlessly modifying product descriptions, making such manipulations hard to detect.In this work, we investigate cognitive biases as black-box adversarial strategies, drawing parallels between their effects on LLMs and human purchasing behavior.Through extensive evaluation across models of varying scale, we find that certain biases, such as social proof, consistently boost product recommendation rate and ranking, while others, like scarcity and exclusivity, surprisingly reduce visibility.Our results demonstrate that cognitive biases are deeply embedded in state-of-the-art LLMs, leading to highly unpredictable behavior in product recommendations and posing significant challenges for effective mitigation. 1 Giorgos Filandrianos, Angeliki Dimitriou, Maria Lymperaiou, Konstantinos Thomas, Giorgos B. Stamou |
EMNLP | 3 |
| 2025 | PAKTON: A Multi-Agent Framework for Question Answering in Long Legal AgreementsabstractContract review is a complex and time-intensive task that typically demands specialized legal expertise, rendering it largely inaccessible to non-experts. Moreover, legal interpretation is rarely straightforward—ambiguity is pervasive, and judgments often hinge on subjective assessments. Compounding these challenges, contracts are usually confidential, restricting their use with proprietary models and necessitating reliance on open-source alternatives. To address these challenges, we introduce PAKTON: a fully open-source, end-to-end, multi-agent framework with plug-and-play capabilities. PAKTON is designed to handle the complexities of contract analysis through collaborative agent workflows and a novel retrieval-augmented generation (RAG) component, enabling automated legal document review that is more accessible, adaptable, and privacy-preserving. Experiments demonstrate that PAKTON outperforms both general-purpose and pretrained models in predictive accuracy, retrieval performance, explainability, completeness, and grounded justifications as evaluated through a human study and validated with automated metrics. Petros Raptopoulos, Giorgos Filandrianos, Maria Lymperaiou, Giorgos B. Stamou |
EMNLP | 3 |
| 2025 | SCENIR: Visual Semantic Clarity through Unsupervised Scene Graph RetrievalabstractDespite 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, such as color. Recognizing the lack of semantic understanding as a key limitation, we propose a novel scene graph-based retrieval framework that emphasizes semantic content over superficial image characteristics. Prior approaches to scene graph retrieval predominantly rely on supervised Graph Neural Networks (GNNs), which require ground truth graph pairs driven from image captions. However, the inconsistency of caption-based supervision stemming from variable text encodings undermine retrieval reliability. To address these, we present SCENIR, a Graph Autoencoder-based unsupervised retrieval framework, which eliminates the dependence on labeled training data. Our model demonstrates superior performance across metrics and runtime efficiency, outperforming existing vision-based, multimodal, and supervised GNN approaches. We further advocate for Graph Edit Distance (GED) as a deterministic and robust ground truth measure for scene graph similarity, replacing the inconsistent caption-based alternatives for the first time in image-to-image retrieval evaluation. Finally, we validate the generalizability of our method by applying it to unannotated datasets via automated scene graph generation, while substantially contributing in advancing state-of-the-art in counterfactual image retrieval. The source code is available at https://github.com/nickhaidos/scenir-icml2025. Nikolaos Chaidos, Angeliki Dimitriou, Maria Lymperaiou, Giorgos B. Stamou |
ICML | 3 |
| 2025 | Analyze-Prompt-Reason: A Collaborative Agent-Based Framework for Multi-Image Vision-Language ReasoningabstractWe present a Collaborative Agent-Based Framework for Multi-Image Reasoning. Our approach tackles the challenge of interleaved multimodal reasoning across diverse datasets and task formats by employing a dual-agent system: a language-based PromptEngineer, which generates context-aware, task-specific prompts, and a VisionReasoner, a large vision-language model (LVLM) responsible for final inference. The framework is fully automated, modular, and training-free, enabling generalization across classification, question answering, and free-form generation tasks involving one or multiple input images. We evaluate our method on 18 diverse datasets from the 2025 MIRAGE Challenge (Track A), covering a broad spectrum of visual reasoning tasks including document QA, visual comparison, dialogue-based understanding, and scene-level inference. Our results demonstrate that LVLMs can effectively reason over multiple images when guided by informative prompts. Notably, Claude 3.7 achieves near-ceiling performance on challenging tasks such as TQA (99.13% accuracy), DocVQA (96.87%), and MMCoQA (75.28 ROUGE-L). We also explore how design choices-such as model selection, shot count, and input length-influence the reasoning performance of different LVLMs. Angelos Vlachos, Giorgos Filandrianos, Maria Lymperaiou, Nikolaos Spanos, Ilias Mitsouras, Vasileios Karampinis, Athanasios Voulodimos |
ACM Multimedia | 3 |
| 2025 | V-CECE: Visual Counterfactual Explanations via Conceptual EditsabstractRecent 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 generation process. We propose a novel, plug-and-play black-box counterfactual generation framework, which suggests step-by-step edits based on theoretical guarantees of optimal edits to produce human-level counterfactual explanations with zero training. Our framework utilizes a pre-trained image editing diffusion model, and operates without access to the internals of the classifier, leading to an explainable counterfactual generation process. Throughout our experimentation, we showcase the explanatory gap between human reasoning and neural model behavior by utilizing both Convolutional Neural Network (CNN), Vision Transformer (ViT) and Large Vision Language Model (LVLM) classifiers, substantiated through a comprehensive human evaluation. Nikolaos Spanos, Maria Lymperaiou, Giorgos Filandrianos, Konstantinos Thomas, Athanasios Voulodimos, Giorgos B. Stamou |
NeurIPS | 2 |
| 2024 | Puzzle Solving using Reasoning of Large Language Models: A SurveyabstractExploring the capabilities of Large Language Models (LLMs) in puzzle solving unveils critical insights into their potential and challenges in AI, marking a significant step towards understanding their applicability in complex reasoning tasks.This survey leverages a unique taxonomy-dividing puzzles into rule-based and rule-less categories-to critically assess LLMs through various methodologies, including prompting techniques, neuro-symbolic approaches, and fine-tuning.Through a critical review of relevant datasets and benchmarks, we assess LLMs' performance, identifying significant challenges in complex puzzle scenarios.Our findings highlight the disparity between LLM capabilities and human-like reasoning, particularly in those requiring advanced logical inference.The survey underscores the necessity for novel strategies and richer datasets to advance LLMs' puzzle-solving proficiency and contribute to AI's logical reasoning and creative problem-solving advancements. Panagiotis Giadikiaroglou, Maria Lymperaiou, Giorgos Filandrianos, Giorgos B. Stamou |
EMNLP | 2 |
| 2024 | Structure Your Data: Towards Semantic Graph CounterfactualsabstractCounterfactual explanations (CEs) based on concepts are explanations that consider alternative scenarios to understand which high-level semantic features contributed to particular model predictions. In this work, we propose CEs based on the semantic graphs accompanying input data to achieve more descriptive, accurate, and human-aligned explanations. Building upon state-of-the-art (SotA) conceptual attempts, we adopt a model-agnostic edit-based approach and introduce leveraging GNNs for efficient Graph Edit Distance (GED) computation. With a focus on the visual domain, we represent images as scene graphs and obtain their GNN embeddings to bypass solving the NP-hard graph similarity problem for all input pairs, an integral part of CE computation process. We apply our method to benchmark and real-world datasets with varying difficulty and availability of semantic annotations. Testing on diverse classifiers, we find that our CEs outperform previous SotA explanation models based on semantics, including both white and black-box as well as conceptual and pixel-level approaches. Their superiority is proven quantitatively and qualitatively, as validated by human subjects, highlighting the significance of leveraging semantic edges in the presence of intricate relationships. Our model-agnostic graph-based approach is widely applicable and easily extensible, producing actionable explanations across different contexts. The code is available at https://github.com/aggeliki-dimitriou/SGCE. Angeliki Dimitriou, Maria Lymperaiou, Giorgos Filandrianos, Konstantinos Thomas, Giorgos B. Stamou |
ICML | 2 |
| 2023 | Large Language Models and Multimodal Retrieval for Visual Word Sense DisambiguationabstractVisual Word Sense Disambiguation (VWSD) is a novel challenging task with the goal of retrieving an image among a set of candidates, which better represents the meaning of an ambiguous word within a given context.In this paper, we make a substantial step towards unveiling this interesting task by applying a varying set of approaches.Since VWSD is primarily a text-image retrieval task, we explore the latest transformer-based methods for multimodal retrieval.Additionally, we utilize Large Language Models (LLMs) as knowledge bases to enhance the given phrases and resolve ambiguity related to the target word.We also study VWSD as a unimodal problem by converting to text-to-text and image-to-image retrieval, as well as question-answering (QA), to fully explore the capabilities of relevant models.To tap into the implicit knowledge of LLMs, we experiment with Chain-of-Thought (CoT) prompting to guide explainable answer generation.On top of all, we train a learn to rank (LTR) model in order to combine our different modules, achieving competitive ranking results.Extensive experiments on VWSD demonstrate valuable insights to effectively drive future directions. Anastasia Kritharoula, Maria Lymperaiou, Giorgos B. Stamou |
EMNLP | 2 |
| 2022 | Towards Explainable Evaluation of Language Models on the Semantic Similarity of Visual ConceptsabstractRecent breakthroughs in NLP research, such as the advent of Transformer models have indisputably contributed to major advancements in several tasks. However, few works research robustness and explainability issues of their evaluation strategies. In this work, we examine the behavior of high-performing pre-trained language models, focusing on the task of semantic similarity for visual vocabularies. First, we address the need for explainable evaluation metrics, necessary for understanding the conceptual quality of retrieved instances. Our proposed metrics provide valuable insights in local and global level, showcasing the inabilities of widely used approaches. Secondly, adversarial interventions on salient query semantics expose vulnerabilities of opaque metrics and highlight patterns in learned linguistic representations. Maria Lymperaiou, George Manoliadis, Orfeas Menis-Mastromichalakis, Edmund Dervakos, Giorgos B. Stamou |
COLING | 1 |