Brazil

Most approaches to role-filler entity extraction (REE) rely on large labeled training corpora in which entity mentions are directly annotated in the input document. In this work, we leverage an existing knowledge base (KB) of entities to perform document-level REE from drug seizure petitions. We propose a system that learns to extract entities from petitions to fill 29 roles of a drug seizure event. Although we have access to a KB covering more than 170 thousand entities and six thousand petitions, such that each entity in the KB is linked to a specific petition, the mentions to an entity within a petition&#39;s text are not annotated. The lack of these annotations brings challenges related to mismatches between entity values in the KB and entity mentions in the documents. Additionally, there are entities with same type or same value. Thus, we propose a distant annotation method to overcome these challenges and automatically label petition documents using the available KB. This annotation method includes a parameter that controls the balance between precision and recall. We also propose a strategy to effectively tune this parameter in order to optimize a given metric. We then train a BERT-based sequence labeling model that learns to identify entity mentions and label them. Our system achieves an F1-score of 78.59 with precision over 82%. We also report ablation studies regarding the distant annotation method.

PROPOR 2022

Entity Extraction from Portuguese Legal Documents Using Distant Supervision

bslm

bert

## Welcome to NAACL 2022!
The Annual Meeting of the North American Chapter of the Association for Computational Linguistics (NAACL) is taking place July 10-15, 2022 as a hybrid event, in Seattle, WA and online. We are happy to welcome all of you to conference! 
 
The main conference program features oral presentations, in-person and virtual posters and demo sessions, a plenary session for our best paper presentations and awards, keynote presentations, a plenary panel on the place of linguistics and symbolic structures in NLP, and an Industrial Track panel on Careers in NLP.
 
Posters (including Findings of NAACL 2022) and demos are grouped by areas for both the in-person and the virtual sessions. For the virtual component, the talks will be on Zoom and the posters and the demos will be in GatherTown. The Student Research Workshop and will have an oral session and a poster session.
 
The program also features 6 Tutorials and 26 Workshops.
 
 We wish you a wonderful conference!
 
[The NAACL 2022 Organizing Committee](https://2022.naacl.org/committees/organization/)

NAACL 2022

2022 Annual Conference of the North American Chapter of the Association for Computational Linguistics

Most approaches to role-filler entity extraction (REE) rely on large labeled training corpora in which entity mentions are directly annotated in the input document. In this work, we leverage an existing knowledge base (KB) of entities to perform document-level REE from drug seizure petitions. We propose a system that learns to extract entities from petitions to fill 29 roles of a drug seizure event. Although we have access to a KB covering more than 170 thousand entities and six thousand petitions, such that each entity in the KB is linked to a specific petition, the mentions to an entity within a petition's text are not annotated. The lack of these annotations brings challenges related to mismatches between entity values in the KB and entity mentions in the documents. Additionally, there are entities with same type or same value. Thus, we propose a distant annotation method to overcome these challenges and automatically label petition documents using the available KB. This annotation method includes a parameter that controls the balance between precision and recall. We also propose a strategy to effectively tune this parameter in order to optimize a given metric. We then train a BERT-based sequence labeling model that learns to identify entity mentions and label them. Our system achieves an F1-score of 78.59 with precision over 82%. We also report ablation studies regarding the distant annotation method.

poster

The International Conference on Computational Processing of Portuguese (PROPOR) is the main event in the area of human language processing that is focused on theoretical and technological issues of written and spoken Portuguese and Galician. The meeting has been a very rich forum for the exchange of ideas and partnerships for the research and industry communities dedicated to the automated processing of Portuguese, promoting the development of methodologies, resources and projects that can be shared among researchers and practitioners in the field.

Find more information and pay the registration fee on [event organizer’s website](https://sites.universidadedefortaleza.com/propor2022/?page_id=401)

The International Conference on Computational Processing of Portuguese (PROPOR) is the main event in the area of human language processing that is focused on theoretical and technological issues of written and spoken Portuguese and Galician.

Wepresent a new resource for discourse studies in Portuguese, the CRPC Discourse Bank (CRPC-DB). CRPC-DB follows the Penn Discourse Treebank style of annotation. The annotation is performed on the PAROLE corpus, a free subset of the Reference Corpus of Con temporary Portuguese (CRPC) that includes news, fiction and didactic/scientific texts. The discourse bank covers explicit and implicit relations at intra and inter-sentential levels, and includes for now a total of 14,436 discourse relations. We present the main guidelines of our annotation and discuss specific cases. An experiment in inter-annotator agreement was performed and holds results of 0.88 F1-score for discourse relation identification, 0.71 Cohen’s K for the classification of discourse relation types, and 0,75 for top-level sense classification. The CRPC-DB will be distributed free of charge through the PORTULAN CLARIN infrastructure.

]CRPC-DB A Discourse Bank for Portuguese

Although very useful, aspect-based sentiment analysis shows several challenges. The occurrence of implicit aspects is one of them. To improve our understanding of implicit aspects, this work analyzes their composition and categorizes the implicit aspect clues found in two corpora of opinionated texts of different domains in the Portuguese language. As results of this work, in addition to the implicit aspect typology, we present four lexicons of implicit aspect clues for different domains and the annotation of implicit aspect clues in an existing corpus.

Implicit opinion aspect clues in Portuguese texts: analysis and categorization

Text classification is an essential task in Natural Language Processing. The researchers and developers need data in the desired language to build new models and algorithms to develop this task. In this presentation, I discuss and make available three datasets of text classification in Portuguese based on data of the B2W group, which is an important contribution to the research in the field.

Should I buy or should I pass: E-Commerce datasets in Portuguese

We report the construction of a web-based Galician corpus and its language model, both made publicly available,by making use of CCNet tools and data. An in-depth analysis of thecorpus is made so as to provide insights on how to achieve optimumquality through the use of heuristics to lower the perplexity.

Revisiting CCNet for Quality Measurements in Galician

We introduce the problem of identifying characters in literary text, and mention some specific issues that are special for Portuguese, in the context of presenting DIP, a shared task to foster work in the area and produce resources for computational literature studies in Portuguese. We describe how the task is organized, the resources that will be created, and how we plan to evaluate the results produced by the participant systems.

Identifying literary characters in Portuguese: Challenges of an international shared task

The lack of a pattern widely accepted in Corpus Linguistics for the construction of text corpora has resulted in multiple possible paths to compilation, resulting in research products that are difficult to interface and have low continuity. The varie-ty of existing corpora aggravates this problem since individual studies use differ-ent forms of expression to describe and solve similar problems. Thus, a gap is identified in the production initiatives to create corpora regarding the “explorato-ry” way of conducting such initiatives. Based on the Lapelinc Workflow for the construction of historical corpora, the Lapelinc Framework presents a working pattern for construction and research activities involving Portuguese language corpora, thereby establishing a set of steps and by-products common to corpora-based linguistic research. Providing a set of tools in the Import Stage with a re-duced learning curve and allowing the convergence of efforts during develop-ment, the Lapelinc Framework tools add functionalities for multiple purposes in the construction of corpora, simplifying the construction of multi-type corpora, facilitated by the resources it makes available.

The systematic construction of multiple types of corpora through the Lapelinc Framework

Deep learning techniques have been shown to be efficient in various tasks, especially in the development of speech recognition systems, that is, systems that aim to transcribe an audio sentence in a sequence of written words. Despite the progress in the area, speech recognition can still be considered difficult, especially for languages lacking available data, such as Brazilian Portuguese (BP). In this sense, this work presents the development of an public Automatic Speech Recognition (ASR) system using only open available audio data, from the fine-tuning of the Wav2vec 2.0 XLSR-53 model pre-trained in many languages, over BP data. The final model presents an average word error rate of 12.4% over 7 different datasets (10.5% when applying a language model). According to our knowledge, the obtained error is the lowest among open end-to-end (E2E) ASR models for BP.

Brazilian Portuguese Speech Recognition Using Wav2vec 2.0

BERT has revolutionized the NLP field by enabling transfer learning with large language models that can capture complex textual patterns, reaching the state-of-the-art for an expressive number of NLP applications. For text classification tasks, BERT has already been extensively explored. However, aspects like how to better cope with the different embeddings provided by the BERT output layer and the usage of language-specific instead of multilingual models are not well studied in the literature, especially for the Brazilian Portuguese language. The purpose of this article is to conduct an extensive experimental study regarding different strategies for aggregating the features produced in the BERT output layer, with a focus on the sentiment analysis task. The experiments include BERT models trained with Brazilian Portuguese corpora and the multilingual version, contemplating multiple aggregation strategies and open-source datasets with predefined training, validation, and test partitions to facilitate the reproducibility of the results. BERT achieved the highest ROC-AUC values for the majority of cases as compared to TF-IDF. Nonetheless, TF-IDF represents a good trade-off between the predictive performance and computational cost.

BERT for Sentiment Analysis: Pre-trained and Fine-Tuned Alternatives

This paper proposes an interface between linguistic concepts and computational interventions to support hate speech detection.
We applied a Natural Language Processing pipeline involving topic modeling and semantic role labeling, allowing a semi-automatic identification of hate speech. We also discuss how such speech qualifies as a type of verbal violence widespread on social networks to reinforce a sexist stereotype. Finally, we use Twitter data to analyze information that resulted in virtual attacks against a specific person.
As an achievement, this work validates the use of linguistic features to annotate data either as hate speech or not. It also proposes using fallacies as a potential additional feature to identify potential intolerant discourses.

Sexist Hate Speech: Identifying Potential Online Verbal Violence Instances

Artificial Intelligence applied to Law is getting attention in the community, both from the Judiciary and the lawyers, due to possible gains in procedural celerity and the automation of repetitive tasks, among other use cases. Many of its bene-fits can be derived from Natural Language Processing since legal proceedings are textual document-based. Named Entity Recognition is the NLP task of identifying and classifying named entities in unstructured text to help achieve these goals. In recent years, transformers emerged as the new state-of-the-art architecture for some tasks in NLP systems. NLP resources in Portuguese, such as models and datasets, are needed to allow Portuguese speaking countries to benefit from this new NLP level. This paper presents the first fine-tuned BERT models trained ex-clusively on Brazilian Portuguese for Legal NER. The models achieved new state-of-the-art on LeNER-Br dataset, a Portuguese NER corpus for the legal domain. We also built a prototype application for Judiciary users to evaluate how the model performed with authentic law documents. The results showed that the models were able to extract information with good quality. Both the models and the prototype application are publicly available for the community.

Premium content

Downloads

Next from PROPOR 2022

]CRPC-DB A Discourse Bank for Portuguese

Similar lecture

SEQZERO: Few-shot Compositional Semantic Parsing with Sequential Prompts and Zero-shot Models