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Enhanced Universal Dependencies (EUD) provide a more informative syntactic representation than Basic Universal Dependencies by relaxing tree constraints to allow for graph structures. While conversion rules from basic to enhanced relations have been established for Portuguese, they were previously evaluated only on journalistic text using gold-standard basic syntactic trees. This paper evaluates the robustness of these rules in diverse scenarios ("in the wild"), encompassing other text genres and domains, as well as realistic parsing pipelines that rely on automatically generated basic syntax. Our results demonstrate that Portuguese-specific rules consistently outperform universal rules. However, the reliance on automatic basic syntax significantly impacts performance. This degradation is particularly severe when the domain of the input text differs from the training data of the basic parser. We also provide a detailed error analysis, identifying specific difficult linguistic phenomena and scenarios.

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Fine-tuned small language models (SLMs) have emerged as effective alternatives for closed-domain tasks, where large language models (LLMs) often lack sufficient parametric knowledge. This study presents a methodology for adapting a small language model to a closed-domain question answering (Q A) task. For each question, the model is trained to output an answer based on the most relevant context passage, among ten provided candidates, thus reproducing the logic of a Retrieval-Augmented Generation (RAG) framework. The fine-tuning data were derived from PetroKGraph, an existing knowledge graph built from Portuguese-language resources in the oil and gas (O G) domain. Experimental results show that the fine-tuned model achieves a 20 percentage points accuracy improvement over the base model on closed-domain questions. It also surpasses GPT-4o and GPT-4o Mini by 12 and 25 points, respectively. Moreover, its performance on general-domain tasks remains comparable to that of the base model, indicating that the specialized model effectively learned domain specific knowledge while maintaining general reasoning capabilities.

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Enhanced Universal Dependencies (EUD) serve as a crucial link between syntax and semantics. Beyond basic syntactic dependencies, EUD provides valuable refined logical connections for downstream tasks such as semantic role labeling, coreference resolution, information extraction, and question answering. The original EUD framework defines six types of relationships, but this paper introduces an extension designed to address subject propagation in pro-drop languages. This "Extended EUD" proposal increases the number of relationships that may be annotated in sentences, improving linguistic representation. Additionally, we report our experiments on a corpus of Portuguese (a pro-drop language), which we make publicly available to the research community.

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Retrieval-Augmented Generation (RAG) has emerged as an effective strategy to ground Large Language Models (LLMs) with reliable, real-time information. This paper investigates the trade-off between cost and performance by evaluating 13 LLMs within a RAG pipeline for the Question Answering (Q&A) task under noisy retrieval conditions. We assess four extractive and nine generative models—spanning both open- and closed-source ones of varying sizes—on a journalistic benchmark specifically designed for RAG. By systematically varying the level of noise injected into the retrieved context, we analyze not only which models perform best, but also their robustness to noisy input. Results show that large open-source generative models (approx. 70B parameters) achieve performance and noise tolerance on par with top-tier closed-source models. However, their computational demands limit their practicality in resource-constrained settings. In contrast, medium-sized open-source models (approx. 7B parameters) emerge as a compelling compromise, balancing efficiency, robustness, and accessibility.

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Sentence simplification (SS) focuses on adapting sentences to enhance their readability and accessibility. While large language models (LLMs) match task-specific baselines in English SS, their performance in Portuguese remains underexplored. This paper presents a comprehensive performance comparison of 26 state-of-the-art LLMs in Portuguese SS, alongside two simplification models trained explicitly for this task and language. They are evaluated under a one-shot setting across scientific, news, and government datasets. We benchmark the models with our newly introduced Gov-Lang-BR corpus (1,703 complex-simple sentence pairs from Brazilian government agencies) and two established datasets: PorSimplesSent and Museum-PT. Our investigation takes advantage of both automatic metrics and large-scale linguistic analysis to examine the transformations achieved by the LLMs. Furthermore, a qualitative assessment of selected generated outputs provides deeper insights into simplification quality. Our findings reveal that while open-source LLMs have achieved impressive results, closed-source LLMs continue to outperform them in Portuguese SS.

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This paper presents (AraSAS) the first open-source Arabic semantic analysis tagging system. AraSAS is a software framework that provides full semantic tagging of text written in Arabic. AraSAS is based on the UCREL Semantic Analysis System (USAS) which was first developed to semantically tag English text. Similarly to USAS, AraSAS uses a hierarchical semantic tag set that contains 21 major discourse fields and 232 fine-grained semantic field tags. The paper describes the creation, validation and evaluation of AraSAS. In addition, we demonstrate a first case study to illustrate the affordances of applying USAS and AraSAS semantic taggers on the Zayed University Arabic-English Bilingual Undergraduate Corpus (ZAEBUC) (Palfreyman and Habash, 2022), where we show and compare the coverage of the two semantic taggers through running them on Arabic and English essays on different topics. The analysis expands to compare the taggers when run on texts in Arabic and English written by the same writer and texts written by male and by female students. Variables for comparison include frequency of use of particular semantic sub-domains, as well as the diversity of semantic elements within a text.

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In this paper we explore the functionalities of ET, a suite designed to support linguistic research and natural language processing tasks using corpora annotated in the CoNLL-U format. These goals are achieved by two integrated environments – Interrogatório, an environment for querying and editing annotated corpora, and Julgamento, an environment for assessing their quality. ET is open-source, built on different Python Web technologies and has Web demonstrations available on-line. ET has been intensively used in our research group for over two years, being the chosen framework for several linguistic and NLP-related studies conducted by its researchers.