206 research outputs found
Information Extraction based on Named Entity for Tourism Corpus
Tourism information is scattered around nowadays. To search for the
information, it is usually time consuming to browse through the results from
search engine, select and view the details of each accommodation. In this
paper, we present a methodology to extract particular information from full
text returned from the search engine to facilitate the users. Then, the users
can specifically look to the desired relevant information. The approach can be
used for the same task in other domains. The main steps are 1) building
training data and 2) building recognition model. First, the tourism data is
gathered and the vocabularies are built. The raw corpus is used to train for
creating vocabulary embedding. Also, it is used for creating annotated data.
The process of creating named entity annotation is presented. Then, the
recognition model of a given entity type can be built. From the experiments,
given hotel description, the model can extract the desired entity,i.e, name,
location, facility. The extracted data can further be stored as a structured
information, e.g., in the ontology format, for future querying and inference.
The model for automatic named entity identification, based on machine learning,
yields the error ranging 8%-25%.Comment: 6 pages, 9 figure
Unsupervised Learning of Discourse Structures using a Tree Autoencoder
Discourse information, as postulated by popular discourse theories, such as
RST and PDTB, has been shown to improve an increasing number of downstream NLP
tasks, showing positive effects and synergies of discourse with important
real-world applications. While methods for incorporating discourse become more
and more sophisticated, the growing need for robust and general discourse
structures has not been sufficiently met by current discourse parsers, usually
trained on small scale datasets in a strictly limited number of domains. This
makes the prediction for arbitrary tasks noisy and unreliable. The overall
resulting lack of high-quality, high-quantity discourse trees poses a severe
limitation to further progress. In order the alleviate this shortcoming, we
propose a new strategy to generate tree structures in a task-agnostic,
unsupervised fashion by extending a latent tree induction framework with an
auto-encoding objective. The proposed approach can be applied to any
tree-structured objective, such as syntactic parsing, discourse parsing and
others. However, due to the especially difficult annotation process to generate
discourse trees, we initially develop a method to generate larger and more
diverse discourse treebanks. In this paper we are inferring general tree
structures of natural text in multiple domains, showing promising results on a
diverse set of tasks.Comment: Accepted to AAAI 2021, 7 page
Discourse analysis of arabic documents and application to automatic summarization
Dans un discours, les textes et les conversations ne sont pas seulement une juxtaposition de mots et de phrases. Ils sont plutôt organisés en une structure dans laquelle des unités de discours sont liées les unes aux autres de manière à assurer à la fois la cohérence et la cohésion du discours. La structure du discours a montré son utilité dans de nombreuses applications TALN, y compris la traduction automatique, la génération de texte et le résumé automatique. L'utilité du discours dans les applications TALN dépend principalement de la disponibilité d'un analyseur de discours performant. Pour aider à construire ces analyseurs et à améliorer leurs performances, plusieurs ressources ont été annotées manuellement par des informations de discours dans des différents cadres théoriques. La plupart des ressources disponibles sont en anglais. Récemment, plusieurs efforts ont été entrepris pour développer des ressources discursives pour d'autres langues telles que le chinois, l'allemand, le turc, l'espagnol et le hindi. Néanmoins, l'analyse de discours en arabe standard moderne (MSA) a reçu moins d'attention malgré le fait que MSA est une langue de plus de 422 millions de locuteurs dans 22 pays. Le sujet de thèse s'intègre dans le cadre du traitement automatique de la langue arabe, plus particulièrement, l'analyse de discours de textes arabes. Cette thèse a pour but d'étudier l'apport de l'analyse sémantique et discursive pour la génération de résumé automatique de documents en langue arabe. Pour atteindre cet objectif, nous proposons d'étudier la théorie de la représentation discursive segmentée (SDRT) qui propose un cadre logique pour la représentation sémantique de phrases ainsi qu'une représentation graphique de la structure du texte où les relations de discours sont de nature sémantique plutôt qu'intentionnelle. Cette théorie a été étudiée pour l'anglais, le français et l'allemand mais jamais pour la langue arabe. Notre objectif est alors d'adapter la SDRT à la spécificité de la langue arabe afin d'analyser sémantiquement un texte pour générer un résumé automatique. Nos principales contributions sont les suivantes : Une étude de la faisabilité de la construction d'une structure de discours récursive et complète de textes arabes. En particulier, nous proposons : Un schéma d'annotation qui couvre la totalité d'un texte arabe, dans lequel chaque constituant est lié à d'autres constituants. Un document est alors représenté par un graphe acyclique orienté qui capture les relations explicites et les relations implicites ainsi que des phénomènes de discours complexes, tels que l'attachement, la longue distance du discours pop-ups et les dépendances croisées. Une nouvelle hiérarchie des relations de discours. Nous étudions les relations rhétoriques d'un point de vue sémantique en se concentrant sur leurs effets sémantiques et non pas sur la façon dont elles sont déclenchées par des connecteurs de discours, qui sont souvent ambigües en arabe.
o une analyse quantitative (en termes de connecteurs de discours, de fréquences de relations, de proportion de relations implicites, etc.) et une analyse qualitative (accord inter-annotateurs et analyse des erreurs) de la campagne d'annotation. Un outil d'analyse de discours où nous étudions à la fois la segmentation automatique de textes arabes en unités de discours minimales et l'identification automatique des relations explicites et implicites du discours. L'utilisation de notre outil pour résumer des textes arabes. Nous comparons la représentation de discours en graphes et en arbres pour la production de résumés.Within a discourse, texts and conversations are not just a juxtaposition of words and sentences. They are rather organized in a structure in which discourse units are related to each other so as to ensure both discourse coherence and cohesion. Discourse structure has shown to be useful in many NLP applications including machine translation, natural language generation and language technology in general. The usefulness of discourse in NLP applications mainly depends on the availability of powerful discourse parsers. To build such parsers and improve their performances, several resources have been manually annotated with discourse information within different theoretical frameworks. Most available resources are in English. Recently, several efforts have been undertaken to develop manually annotated discourse information for other languages such as Chinese, German, Turkish, Spanish and Hindi. Surprisingly, discourse processing in Modern Standard Arabic (MSA) has received less attention despite the fact that MSA is a language with more than 422 million speakers in 22 countries. Computational processing of Arabic language has received a great attention in the literature for over twenty years. Several resources and tools have been built to deal with Arabic non concatenative morphology and Arabic syntax going from shallow to deep parsing. However, the field is still very vacant at the layer of discourse. As far as we know, the sole effort towards Arabic discourse processing was done in the Leeds Arabic Discourse Treebank that extends the Penn Discourse TreeBank model to MSA. In this thesis, we propose to go beyond the annotation of explicit relations that link adjacent units, by completely specifying the semantic scope of each discourse relation, making transparent an interpretation of the text that takes into account the semantic effects of discourse relations. In particular, we propose the first effort towards a semantically driven approach of Arabic texts following the Segmented Discourse Representation Theory (SDRT). Our main contributions are: A study of the feasibility of building a recursive and complete discourse structures of Arabic texts. In particular, we propose: An annotation scheme for the full discourse coverage of Arabic texts, in which each constituent is linked to other constituents. A document is then represented by an oriented acyclic graph, which captures explicit and implicit relations as well as complex discourse phenomena, such as long-distance attachments, long-distance discourse pop-ups and crossed dependencies. A novel discourse relation hierarchy. We study the rhetorical relations from a semantic point of view by focusing on their effect on meaning and not on how they are lexically triggered by discourse connectives that are often ambiguous, especially in Arabic. A thorough quantitative analysis (in terms of discourse connectives, relation frequencies, proportion of implicit relations, etc.) and qualitative analysis (inter-annotator agreements and error analysis) of the annotation campaign. An automatic discourse parser where we investigate both automatic segmentation of Arabic texts into elementary discourse units and automatic identification of explicit and implicit Arabic discourse relations. An application of our discourse parser to Arabic text summarization. We compare tree-based vs. graph-based discourse representations for producing indicative summaries and show that the full discourse coverage of a document is definitively a plus
StyloThai: A scalable framework for stylometric authorship identification of Thai documents
This is an accepted manuscript of an article published by ACM in ACM Transactions on Asian and Low-Resource Language Information Processing in January 2020, available online: https://doi.org/10.1145/3365832
The accepted version of the publication may differ from the final published version.© 2020 Association for Computing Machinery. All rights reserved. Authorship identification helps to identify the true author of a given anonymous document from a set of candidate authors. The applications of this task can be found in several domains, such as law enforcement agencies and information retrieval. These application domains are not limited to a specific language, community, or ethnicity. However, most of the existing solutions are designed for English, and a little attention has been paid to Thai. These existing solutions are not directly applicable to Thai due to the linguistic differences between these two languages. Moreover, the existing solution designed for Thai is unable to (i) handle outliers in the dataset, (ii) scale when the size of the candidate authors set increases, and (iii) perform well when the number of writing samples for each candidate author is low.We identify a stylometric feature space for the Thai authorship identification task. Based on our feature space, we present an authorship identification solution that uses the probabilistic k nearest neighbors classifier by transforming each document into a collection of point sets. Specifically, this document transformation allows us to (i) use set distance measures associated with an outlier handling mechanism, (ii) capture stylistic variations within a document, and (iii) produce multiple predictions for a query document. We create a new Thai authorship identification corpus containing 547 documents from 200 authors, which is significantly larger than the corpus used by the existing study (an increase of 32 folds in terms of the number of candidate authors). The experimental results show that our solution can overcome the limitations of the existing solution and outperforms all competitors with an accuracy level of 91.02%. Moreover, we investigate the effectiveness of each stylometric features category with the help of an ablation study. We found that combining all categories of the stylometric features outperforms the other combinations. Finally, we cross compare the feature spaces and classification methods of all solutions. We found that (i) our solution can scale as the number of candidate authors increases, (ii) our method outperforms all the competitors, and (iii) our feature space provides better performance than the feature space used by the existing study.The research was partially supported by the Digital Economy Promotion Agency (project# MP-62- 0003); and Thailand Research Fund and Office of the Higher Education Commission (MRG6180266).Published versio
Satellite Workshop On Language, Artificial Intelligence and Computer Science for Natural Language Processing Applications (LAICS-NLP): Discovery of Meaning from Text
This paper proposes a novel method to disambiguate important words from a collection of documents. The
hypothesis that underlies this approach is that there is a
minimal set of senses that are significant in characterizing a context. We extend Yarowsky’s one sense
per discourse [13] further to a collection of related
documents rather than a single document. We perform
distributed clustering on a set of features representing
each of the top ten categories of documents in the
Reuters-21578 dataset. Groups of terms that have a
similar term distributional pattern across documents were
identified. WordNet-based similarity measurement was
then computed for terms within each cluster. An
aggregation of the associations in WordNet that was
employed to ascertain term similarity within clusters has
provided a means of identifying clusters’ root senses
- …