activity
20232026
most citedLeak, Cheat, Repeat: Data Contamination and Evaluation Malpractices in Closed-Source LLMs

19 citations · 34 across the 22 of their papers we have counts for

collaborators

22 papers

cs.CL2026

Last Translation Benchmark

Vilém Zouhar, Niyati Bafna, Mukund Choudhary +263

For scientific progress, we need benchmarks that test the limits of state-of-the-art models, and evaluation methods that inform us about failure cases. As models get stronger, stan…

cs.CL2026

VetScore: Risk-Weighted Fact Verification for Veterinary Long-Form QA with Citations

Ivan Kartáč, Jan Tovarys, Mateusz Lango +1

Citation excerpts can be used to increase the reliability of generated outputs and their faithfulness to cited sources, which is especially important in high-stakes domains such as…

cs.CL2026

PluraMath: Extending Mathematical Reasoning Evaluation Beyond High-Resource Languages

Daryna Dementieva, Nikolay Babakov, Kathy Hämmerl +14

Mathematical reasoning has become a central task for evaluating and tuning reasoning Large Language Models (LLMs), yet existing benchmarks remain heavily biased toward high-resourc…

cs.CL2026

UFAL-CUNI at SemEval-2026 Task 11: An Efficient Modular Neuro-symbolic Method for Syllogistic Reasoning

Ivan Kartáč, Kristýna Onderková, Jan Bronec +3

This paper describes our system submitted to SemEval-2026 Task 11: Disentangling Content and Formal Reasoning in Large Language Models. We present an efficient modular neuro-symbol…

cs.CL2026

Reasoning Gets Harder for LLMs Inside A Dialogue

Ivan Kartáč, Mateusz Lango, Ondřej Dušek

Large Language Models (LLMs) achieve strong performance on many reasoning benchmarks, yet these evaluations typically focus on isolated tasks that differ from real-world usage in t…

cs.CL2025★ 1 cited

SRS-Stories: Vocabulary-constrained multilingual story generation for language learning

Wiktor Kamzela, Mateusz Lango, Ondrej Dusek

In this paper, we use large language models to generate personalized stories for language learners, using only the vocabulary they know. The generated texts are specifically writte…

cs.CL2025

LLM Agents Implement an NLG System from Scratch: Building Interpretable Rule-Based RDF-to-Text Generators

Mateusz Lango, Ondřej Dušek

We present a novel neurosymbolic framework for RDF-to-text generation, in which the model is "trained" through collaborative interactions among multiple LLM agents rather than trad…

cs.CL2025

OpeNLGauge: An Explainable Metric for NLG Evaluation with Open-Weights LLMs

Ivan Kartáč, Mateusz Lango, Ondřej Dušek

Large Language Models (LLMs) have demonstrated great potential as evaluators of NLG systems, allowing for high-quality, reference-free, and multi-aspect assessments. However, exist…

cs.CL2025

Leveraging Large Language Models for Building Interpretable Rule-Based Data-to-Text Systems

Jędrzej Warczyński, Mateusz Lango, Ondrej Dusek

We introduce a simple approach that uses a large language model (LLM) to automatically implement a fully interpretable rule-based data-to-text system in pure Python. Experimental e…

cs.CL2025

Polish-ASTE: Aspect-Sentiment Triplet Extraction Datasets for Polish

Marta Lango, Borys Naglik, Mateusz Lango +1

Aspect-Sentiment Triplet Extraction (ASTE) is one of the most challenging and complex tasks in sentiment analysis. It concerns the construction of triplets that contain an aspect,…

cs.CL2024

ASTE Transformer Modelling Dependencies in Aspect-Sentiment Triplet Extraction

Iwo Naglik, Mateusz Lango

Aspect-Sentiment Triplet Extraction (ASTE) is a recently proposed task of aspect-based sentiment analysis that consists in extracting (aspect phrase, opinion phrase, sentiment pola…

cs.LG2024★ 2 cited

Counterfactual Explanations with Probabilistic Guarantees on their Robustness to Model Change

Ignacy Stępka, Mateusz Lango, Jerzy Stefanowski

Counterfactual explanations (CFEs) guide users on how to adjust inputs to machine learning models to achieve desired outputs. While existing research primarily addresses static sce…

cs.CL2024★ 1 cited

A Survey of Text Style Transfer: Applications and Ethical Implications

Sourabrata Mukherjee, Mateusz Lango, Zdenek Kasner +1

Text style transfer (TST) is an important task in controllable text generation, which aims to control selected attributes of language use, such as politeness, formality, or sentime…

cs.AI2024

Faithful and Plausible Natural Language Explanations for Image Classification: A Pipeline Approach

Adam Wojciechowski, Mateusz Lango, Ondrej Dusek

Existing explanation methods for image classification struggle to provide faithful and plausible explanations. This paper addresses this issue by proposing a post-hoc natural langu…

cs.CL2024★ 1 cited

Generating clickbait spoilers with an ensemble of large language models

Mateusz Woźny, Mateusz Lango

Clickbait posts are a widespread problem in the webspace. The generation of spoilers, i.e. short texts that neutralize clickbait by providing information that satisfies the curiosi…

cs.LG2024★ 8 cited

A multi-criteria approach for selecting an explanation from the set of counterfactuals produced by an ensemble of explainers

Ignacy Stępka, Mateusz Lango, Jerzy Stefanowski

Counterfactuals are widely used to explain ML model predictions by providing alternative scenarios for obtaining the more desired predictions. They can be generated by a variety of…

cs.CL2024★ 19 cited

Leak, Cheat, Repeat: Data Contamination and Evaluation Malpractices in Closed-Source LLMs

Simone Balloccu, Patrícia Schmidtová, Mateusz Lango +1

Natural Language Processing (NLP) research is increasingly focusing on the use of Large Language Models (LLMs), with some of the most popular ones being either fully or partially c…

cs.LG2023

Deep Similarity Learning Loss Functions in Data Transformation for Class Imbalance

Damian Horna, Lango Mateusz, Jerzy Stefanowski

Improving the classification of multi-class imbalanced data is more difficult than its two-class counterpart. In this paper, we use deep neural networks to train new representation…

cs.CL2023

The Problem of Coherence in Natural Language Explanations of Recommendations

Jakub Raczyński, Mateusz Lango, Jerzy Stefanowski

Providing natural language explanations for recommendations is particularly useful from the perspective of a non-expert user. Although several methods for providing such explanatio…

cs.CL2023

Critic-Driven Decoding for Mitigating Hallucinations in Data-to-text Generation

Mateusz Lango, Ondřej Dušek

Hallucination of text ungrounded in the input is a well-known problem in neural data-to-text generation. Many methods have been proposed to mitigate it, but they typically require…

cs.CL2023

With a Little Help from the Authors: Reproducing Human Evaluation of an MT Error Detector

Ondřej Plátek, Mateusz Lango, Ondřej Dušek

This work presents our efforts to reproduce the results of the human evaluation experiment presented in the paper of Vamvas and Sennrich (2022), which evaluated an automatic system…

cs.CL2023★ 2 cited

Three Ways of Using Large Language Models to Evaluate Chat

Ondřej Plátek, Vojtěch Hudeček, Patricia Schmidtová +2

This paper describes the systems submitted by team6 for ChatEval, the DSTC 11 Track 4 competition. We present three different approaches to predicting turn-level qualities of chatb…