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Dissertations / Theses on the topic 'Arabic Natural Language Processing'
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Alabbas, Maytham Abualhail Shahed. "Textual entailment for modern standard Arabic." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/textual-entailment-for-modern-standard-arabic(9e053b1a-0570-4c30-9100-3d9c2ba86d8c).html.
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This thesis explores a range of approaches to the task of recognising textual entailment (RTE), i.e. determining whether one text snippet entails another, for Arabic, where we are faced with an exceptional level of lexical and structural ambiguity. To the best of our knowledge, this is the first attempt to carry out this task for Arabic. Tree edit distance (TED) has been widely used as a component of natural language processing (NLP) systems that attempt to achieve the goal above, with the distance between pairs of dependency trees being taken as a measure of the likelihood that one entails the other. Such a technique relies on having accurate linguistic analyses. Obtaining such analyses for Arabic is notoriously difficult. To overcome these problems we have investigated strategies for improving tagging and parsing depending on system combination techniques. These strategies lead to substantially better performance than any of the contributing tools. We describe also a semi-automatic technique for creating a first dataset for RTE for Arabic using an extension of the ‘headline-lead paragraph’ technique because there are, again to the best of our knowledge, no such datasets available. We sketch the difficulties inherent in volunteer annotators-based judgment, and describe a regime to ameliorate some of these. The major contribution of this thesis is the introduction of two ways of improving the standard TED: (i) we present a novel approach, extended TED (ETED), for extending the standard TED algorithm for calculating the distance between two trees by allowing operations to apply to subtrees, rather than just to single nodes. This leads to useful improvements over the performance of the standard TED for determining entailment. The key here is that subtrees tend to correspond to single information units. By treating operations on subtrees as less costly than the corresponding set of individual node operations, ETED concentrates on entire information units, which are a more appropriate granularity than individual words for considering entailment relations; and (ii) we use the artificial bee colony (ABC) algorithm to automatically estimate the cost of edit operations for single nodes and subtrees and to determine thresholds, since assigning an appropriate cost to each edit operation manually can become a tricky task.The current findings are encouraging. These extensions can substantially affect the F-score and accuracy and achieve a better RTE model when compared with a number of string-based algorithms and the standard TED approaches. The relative performance of the standard techniques on our Arabic test set replicates the results reported for these techniques for English test sets. We have also applied ETED with ABC to the English RTE2 test set, where it again outperforms the standard TED.
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Khaliq, Bilal. "Unsupervised learning of Arabic non-concatenative morphology." Thesis, University of Sussex, 2015. http://sro.sussex.ac.uk/id/eprint/53865/.
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Unsupervised approaches to learning the morphology of a language play an important role in computer processing of language from a practical and theoretical perspective, due their minimal reliance on manually produced linguistic resources and human annotation. Such approaches have been widely researched for the problem of concatenative affixation, but less attention has been paid to the intercalated (non-concatenative) morphology exhibited by Arabic and other Semitic languages. The aim of this research is to learn the root and pattern morphology of Arabic, with accuracy comparable to manually built morphological analysis systems. The approach is kept free from human supervision or manual parameter settings, assuming only that roots and patterns intertwine to form a word. Promising results were obtained by applying a technique adapted from previous work in concatenative morphology learning, which uses machine learning to determine relatedness between words. The output, with probabilistic relatedness values between words, was then used to rank all possible roots and patterns to form a lexicon. Analysis using trilateral roots resulted in correct root identification accuracy of approximately 86% for inflected words. Although the machine learning-based approach is effective, it is conceptually complex. So an alternative, simpler and computationally efficient approach was then devised to obtain morpheme scores based on comparative counts of roots and patterns. In this approach, root and pattern scores are defined in terms of each other in a mutually recursive relationship, converging to an optimized morpheme ranking. This technique gives slightly better accuracy while being conceptually simpler and more efficient. The approach, after further enhancements, was evaluated on a version of the Quranic Arabic Corpus, attaining a final accuracy of approximately 93%. A comparative evaluation shows this to be superior to two existing, well used manually built Arabic stemmers, thus demonstrating the practical feasibility of unsupervised learning of non-concatenative morphology.
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Feddag, Allel. "New models for Arabic and English natural languages for computer applications." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334985.
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Kan'an, Tarek Ghaze. "Arabic News Text Classification and Summarization: A Case of the Electronic Library Institute SeerQ (ELISQ)." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/74272.
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Arabic news articles in heterogeneous electronic collections are difficult for users to work with. Two problems are: that they are not categorized in a way that would aid browsing, and that there are no summaries or detailed metadata records that could be easier to work with than full articles. To address the first problem, schema mapping techniques were adapted to construct a simple taxonomy for Arabic news stories that is compatible with the subject codes of the International Press Telecommunications Council. So that each article would be labeled with the proper taxonomy category, automatic classification methods were researched, to identify the most appropriate. Experiments showed that the best features to use in classification resulted from a new tailored stemming approach (i.e., a new Arabic light stemmer called P-Stemmer). When coupled with binary classification using SVM, the newly developed approach proved to be superior to state-of-the-art techniques. To address the second problem, i.e., summarization, preliminary work was done with English corpora. This was in the context of a new Problem Based Learning (PBL) course wherein students produced template summaries of big text collections. The techniques used in the course were extended to work with Arabic news. Due to the lack of high quality tools for Named Entity Recognition (NER) and topic identification for Arabic, two new tools were constructed: RenA for Arabic NER, and ALDA for Arabic topic extraction tool (using the Latent Dirichlet Algorithm). Controlled experiments with each of RenA and ALDA, involving Arabic speakers and a randomly selected corpus of 1000 Qatari news articles, showed the tools produced very good results (i.e., names, organizations, locations, and topics). Then the categorization, NER, topic identification, and additional information extraction techniques were combined to produce approximately 120,000 summaries for Qatari news articles, which are searchable, along with the articles, using LucidWorks Fusion, which builds upon Solr software. Evaluation of the summaries showed high ratings based on the 1000-article test corpus. Contributions of this research with Arabic news articles thus include a new: test corpus, taxonomy, light stemmer, classification approach, NER tool, topic identification tool, and template-based summarizer – all shown through experimentation to be highly effective.<br>Ph. D.
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Benajiba, Yassine. "Arabic named entity recognition." Doctoral thesis, Universitat Politècnica de València, 2010. http://hdl.handle.net/10251/8318.
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En esta tesis doctoral se describen las investigaciones realizadas con el objetivo de determinar
las mejores tecnicas para construir un Reconocedor de Entidades Nombradas
en Arabe. Tal sistema tendria la habilidad de identificar y clasificar las entidades
nombradas que se encuentran en un texto arabe de dominio abierto.
La tarea de Reconocimiento de Entidades Nombradas (REN) ayuda a otras tareas de
Procesamiento del Lenguaje Natural (por ejemplo, la Recuperacion de Informacion, la
Busqueda de Respuestas, la Traduccion Automatica, etc.) a lograr mejores resultados
gracias al enriquecimiento que a~nade al texto. En la literatura existen diversos trabajos
que investigan la tarea de REN para un idioma especifico o desde una perspectiva
independiente del lenguaje. Sin embargo, hasta el momento, se han publicado muy
pocos trabajos que estudien dicha tarea para el arabe.
El arabe tiene una ortografia especial y una morfologia compleja, estos aspectos aportan
nuevos desafios para la investigacion en la tarea de REN. Una investigacion completa
del REN para elarabe no solo aportaria las tecnicas necesarias para conseguir
un alto rendimiento, sino que tambien proporcionara un analisis de los errores y una
discusion sobre los resultados que benefician a la comunidad de investigadores del
REN. El objetivo principal de esta tesis es satisfacer esa necesidad. Para ello hemos:
1. Elaborado un estudio de los diferentes aspectos del arabe relacionados con dicha
tarea;
2. Analizado el estado del arte del REN;
3. Llevado a cabo una comparativa de los resultados obtenidos por diferentes
tecnicas de aprendizaje automatico;
4. Desarrollado un metodo basado en la combinacion de diferentes clasificadores,
donde cada clasificador trata con una sola clase de entidades nombradas y emplea
el conjunto de caracteristicas y la tecnica de aprendizaje automatico mas
adecuados para la clase de entidades nombradas en cuestion.
Nuestros experimentos han sido evaluados sobre nueve conjuntos de test.<br>Benajiba, Y. (2009). Arabic named entity recognition [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8318<br>Palancia
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Sabtan, Yasser Muhammad Naguib mahmoud. "Lexical selection for machine translation." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/lexical-selection-for-machine-translation(28ea687c-5eaf-4412-992a-16fc88b977c8).html.
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Current research in Natural Language Processing (NLP) tends to exploit corpus resources as a way of overcoming the problem of knowledge acquisition. Statistical analysis of corpora can reveal trends and probabilities of occurrence, which have proved to be helpful in various ways. Machine Translation (MT) is no exception to this trend. Many MT researchers have attempted to extract knowledge from parallel bilingual corpora. The MT problem is generally decomposed into two sub-problems: lexical selection and reordering of the selected words. This research addresses the problem of lexical selection of open-class lexical items in the framework of MT. The work reported in this thesis investigates different methodologies to handle this problem, using a corpus-based approach. The current framework can be applied to any language pair, but we focus on Arabic and English. This is because Arabic words are hugely ambiguous and thus pose a challenge for the current task of lexical selection. We use a challenging Arabic-English parallel corpus, containing many long passages with no punctuation marks to denote sentence boundaries. This points to the robustness of the adopted approach. In our attempt to extract lexical equivalents from the parallel corpus we focus on the co-occurrence relations between words. The current framework adopts a lexicon-free approach towards the selection of lexical equivalents. This has the double advantage of investigating the effectiveness of different techniques without being distracted by the properties of the lexicon and at the same time saving much time and effort, since constructing a lexicon is time-consuming and labour-intensive. Thus, we use as little, if any, hand-coded information as possible. The accuracy score could be improved by adding hand-coded information. The point of the work reported here is to see how well one can do without any such manual intervention. With this goal in mind, we carry out a number of preprocessing steps in our framework. First, we build a lexicon-free Part-of-Speech (POS) tagger for Arabic. This POS tagger uses a combination of rule-based, transformation-based learning (TBL) and probabilistic techniques. Similarly, we use a lexicon-free POS tagger for English. We use the two POS taggers to tag the bi-texts. Second, we develop lexicon-free shallow parsers for Arabic and English. The two parsers are then used to label the parallel corpus with dependency relations (DRs) for some critical constructions. Third, we develop stemmers for Arabic and English, adopting the same knowledge -free approach. These preprocessing steps pave the way for the main system (or proposer) whose task is to extract translational equivalents from the parallel corpus. The framework starts with automatically extracting a bilingual lexicon using unsupervised statistical techniques which exploit the notion of co-occurrence patterns in the parallel corpus. We then choose the target word that has the highest frequency of occurrence from among a number of translational candidates in the extracted lexicon in order to aid the selection of the contextually correct translational equivalent. These experiments are carried out on either raw or POS-tagged texts. Having labelled the bi-texts with DRs, we use them to extract a number of translation seeds to start a number of bootstrapping techniques to improve the proposer. These seeds are used as anchor points to resegment the parallel corpus and start the selection process once again. The final F-score for the selection process is 0.701. We have also written an algorithm for detecting ambiguous words in a translation lexicon and obtained a precision score of 0.89.
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Trotter, William. "Translation Salience: A Model of Equivalence in Translation (Arabic/English)." University of Sydney. School of European, Asian and Middle Eastern Languages, 2000. http://hdl.handle.net/2123/497.
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The term equivalence describes the relationship between a translation and the text from which it is translated. Translation is generally viewed as indeterminate insofar as there is no single acceptable translation - but many. Despite this, the rationalist metaphor of translation equivalence prevails. Rationalist approaches view translation as a process in which an original text is analysed to a level of abstraction, then transferred into a second representation from which a translation is generated. At the deepest level of abstraction, representations for analysis and generation are identical and transfer becomes redundant, while at the surface level it is said that surface textual features are transferred directly. Such approaches do not provide a principled explanation of how or why abstraction takes place in translation. They also fail to resolve the dilemma of specifying the depth of transfer appropriate for a given translation task. By focusing on the translator�s role as mediator of communication, equivalence can be understood as the coordination of information about situations and states of mind. A fundamental opposition is posited between the transfer of rule-like or codifiable aspects of equivalence and those non-codifiable aspects in which salient information is coordinated. The Translation Salience model proposes that Transfer and Salience constitute bipolar extremes of a continuum. The model offers a principled account of the translator�s interlingual attunement to multi-placed coordination, proposing that salient information can be accounted for with three primary notions: markedness, implicitness and localness. Chapter Two develops the Translation Salience model. The model is supported with empirical evidence from published translations of Arabic and English texts. Salience is illustrated in Chapter Three through contextualized interpretations associated with various Arabic communication resources (repetition, code switching, agreement, address in relative clauses, and the disambiguation of presentative structures). Measurability of the model is addressed in Chapter Four with reference to emerging computational techniques. Further research is suggested in connection with theme and focus, text type, cohesion and collocation relations.
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Lameris, Harm. "Homograph Disambiguation and Diacritization for Arabic Text-to-Speech Using Neural Networks." Thesis, Uppsala universitet, Institutionen för lingvistik och filologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446509.
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Pre-processing Arabic text for Text-to-Speech (TTS) systems poses major challenges, as Arabic omits short vowels in writing. This omission leads to a large number of homographs, and means that Arabic text needs to be diacritized to disambiguate these homographs, in order to be matched up with the intended pronunciation. Diacritizing Arabic has generally been achieved by using rule-based, statistical, or hybrid methods that combine rule-based and statistical methods. Recently, diacritization methods involving deep learning have shown promise in reducing error rates. These deep-learning methods are not yet commonly used in TTS engines, however. To examine neural diacritization methods for use in TTS engines, we normalized and pre-processed a version of the Tashkeela corpus, a large diacritized corpus containing largely Classical Arabic texts, for TTS purposes. We then trained and tested three state-of-the-art Recurrent-Neural-Network-based models on this data set. Additionally we tested these models on the Wiki News corpus, a test set that contains Modern Standard Arabic (MSA) news articles and thus more closely resembles most TTS queries. The models were evaluated by comparing the Diacritic Error Rate (DER) and Word Error Rate (WER) achieved for each data set to one another and to the DER and WER reported in the original papers. Moreover, the per-diacritic accuracy was examined, and a manual evaluation was performed. For the Tashkeela corpus, all models achieved a lower DER and WER than reported in the original papers. This was largely the result of using more training data in addition to the TTS pre-processing steps that were performed on the data. For the Wiki News corpus, the error rates were higher, largely due to the domain gap between the data sets. We found that for both data sets the models overfit on common patterns and the most common diacritic. For the Wiki News corpus the models struggled with Named Entities and loanwords. Purely neural models generally outperformed the model that combined deep learning with rule-based and statistical corrections. These findings highlight the usability of deep learning methods for Arabic diacritization in TTS engines as well as the need for diacritized corpora that are more representative of Modern Standard Arabic.
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Saadane, Houda. "Le traitement automatique de l’arabe dialectalisé : aspects méthodologiques et algorithmiques." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAL022/document.
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El, Hage Antoine. "L’Informatique au service des sciences du langage : la conception d’un programme étudiant le parler arabe libanais blanc." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCD005/document.
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A une époque où l’informatique a envahi tous les aspects de notre vie quotidienne, il est tout à fait normal de voir le domaine informatique participer aux travaux en sciences humaines et sociales, et notamment en linguistique où le besoin de développer des logiciels informatiques se fait de plus en plus pressant avec le volume grandissant des corpus traités. D’où notre travail de thèse qui consiste en l’élaboration d’un programme EPL qui étudie le parler arabe libanais blanc. En partant d’un corpus élaboré à partir de deux émissions télévisées enregistrées puis transcrites en lettres arabes, ce programme, élaboré avec le logiciel Access, nous a permis d’extraire les mots et les collocations et de procéder à une analyse linguistique aux niveaux lexical, phonétique, syntaxique et collocationnel. Le fonctionnement de l’EPL ainsi que le code de son développement sont décrits en détails dans une partie informatique à part. Des annexes de taille closent la thèse et rassemblent le produit des travaux de toute une équipe de chercheures venant de maintes spécialités<br>At a time when computer science has invaded all aspects of our daily life, it is natural to see the computer field participating in human and social sciences work, and more particularly in linguistics where the need to develop computer software is becoming more and more pressing with the growing volume of analyzed corpora. Hence our thesis which consists in elaborating a program EPL that studies the white Lebanese Arabic speech. Starting from a corpus elaborated from two TV programs recorded then transcribed in Arabic letters, the program EPL, developed with Access software, allowed us to extract words and collocations, and to carry out a linguistic analysis on the lexical, phonetic, syntactic and collocational levels. The EPL’s functioning as well as its development code are described in the computer part. Important annexes conclude the thesis and gather the result of the work of a team of researchers coming from different specialties
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Hamdi, Ahmed. "Traitement automatique du dialecte tunisien à l'aide d'outils et de ressources de l'arabe standard : application à l'étiquetage morphosyntaxique." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4089/document.
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Le développement d’outils de traitement automatique pour les dialectes de l’arabe se heurte à l’absence de ressources pour ces derniers. Comme conséquence d’une situation de diglossie, il existe une variante de l’arabe, l’arabe moderne standard, pour laquelle de nombreuses ressources ont été développées et ont permis de construire des outils de traitement automatique de la langue. Étant donné la proximité des dialectes de l’arabe, avec l’arabe moderne standard, une voie consiste à réaliser une conversion surfacique du dialecte vers l’arabe mo- derne standard afin de pouvoir utiliser les outils existants pour l’arabe standard. Dans ce travail, nous nous intéressons particulièrement au traitement du dialecte tunisien. Nous proposons un système de conversion du tunisien vers une forme approximative de l’arabe standard pour laquelle l’application des outils conçus pour ce dernier permet d’obtenir de bons résultats. Afin de valider cette approche, nous avons eu recours à un étiqueteur morphosyntaxique conçu pour l’étiquetage de l’arabe standard. Ce dernier permet d’assigner des étiquettes morphosyntaxiques à la sortie de notre système de conver- sion. Ces étiquettes sont finalement projetées sur le tunisien. Notre système atteint une précision de 89% suite à la conversion qui repré- sente une augmentation absolue de ∼20% par rapport à l’étiquetage d’avant la conversion<br>Developing natural language processing tools usually requires a large number of resources (lexica, annotated corpora, ...), which often do not exist for less- resourced languages. One way to overcome the problem of lack of resources is to devote substantial efforts to build new ones from scratch. Another approach is to exploit existing resources of closely related languages. Taking advantage of the closeness of standard Arabic and its dialects, one way to solve the problem of limited resources, consists in performing a conversion of Arabic dialects into standard Arabic in order to use the tools developed to handle the latter. In this work, we focus especially on processing Tunisian Arabic dialect. We propose a conversion system of Tunisian into a closely form of standard Arabic for which the application of natural language processing tools designed for the latter provides good results. In order to validate our approach, we focused on part-of-speech tagging. Our system achieved an accuracy of 89% which presents ∼20% of absolute improvement over a standard Arabic tagger baseline
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Al-Khonaizi, Mohammed Taqi. "Natural Arabic language text understanding." Thesis, University of Greenwich, 1999. http://gala.gre.ac.uk/6096/.
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The most challenging part of natural language understanding is the representation of meaning. The current representation techniques are not sufficient to resolve the ambiguities, especially when the meaning is to be used for interrogation at a later stage. Arabic language represents a challenging field for Natural Language Processing (NLP) because of its rich eloquence and free word order, but at the same time it is a good platform to capture understanding because of its rich computational, morphological and grammar rules. Among different representation techniques, Lexical Functional Grammar (LFG) theory is found to be best suited for this task because of its structural approach. LFG lays down a computational approach towards NLP, especially the constituent and the functional structures, and models the completeness of relationships among the contents of each structure internally, as well as among the structures externally. The introduction of Artificial Intelligence (AI) techniques, such as knowledge representation and inferencing, enhances the capture of meaning by utilising domain specific common sense knowledge embedded in the model of domain of discourse and the linguistic rules that have been captured from the Arabic language grammar. This work has achieved the following results: (i) It is the first attempt to apply the LFG formalism on a full Arabic declarative text that consists of more than one paragraph. (ii) It extends the semantic structure of the LFG theory by incorporating a representation based on the thematic-role frames theory. (iii) It extends to the LFG theory to represent domain specific common sense knowledge. (iv) It automates the production process of the functional and semantic structures. (v) It automates the production process of domain specific common sense knowledge structure, which enhances the understanding ability of the system and resolves most ambiguities in subsequent question-answer sessions.
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El, Mahdaouy Abdelkader. "Accès à l'information dans les grandes collections textuelles en langue arabe." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAM091/document.
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Face à la quantité d'information textuelle disponible sur le web en langue arabe, le développement des Systèmes de Recherche d'Information (SRI) efficaces est devenu incontournable pour retrouver l'information pertinente. La plupart des SRIs actuels de la langue arabe reposent sur la représentation par sac de mots et l'indexation des documents et des requêtes est effectuée souvent par des mots bruts ou des racines. Ce qui conduit à plusieurs problèmes tels que l'ambigüité et la disparité des termes, etc.Dans ce travail de thèse, nous nous sommes intéressés à apporter des solutions aux problèmes d'ambigüité et de disparité des termes pour l'amélioration de la représentation des documents et le processus de l'appariement des documents et des requêtes. Nous apportons quatre contributions au niveau de processus de représentation, d'indexation et de recherche d'information en langue arabe. La première contribution consiste à représenter les documents à la fois par des termes simples et des termes complexes. Cela est justifié par le fait que les termes simples seuls et isolés de leur contexte sont ambigus et moins précis pour représenter le contenu des documents. Ainsi, nous avons proposé une méthode hybride pour l’extraction de termes complexes en langue arabe, en combinant des propriétés linguistiques et des modèles statistiques. Le filtre linguistique repose à la fois sur l'étiquetage morphosyntaxique et la prise en compte des variations pour sélectionner les termes candidats. Pour sectionner les termes candidats pertinents, nous avons introduit une mesure d'association permettant de combiner l'information contextuelle avec les degrés de spécificité et d'unité. La deuxième contribution consiste à explorer et évaluer les systèmes de recherche d’informations permettant de tenir compte de l’ensemble des éléments d’indexation (termes simples et complexes). Par conséquent, nous étudions plusieurs extensions des modèles existants de RI pour l'intégration des termes complexes. En outre, nous explorons une panoplie de modèles de proximité. Pour la prise en compte des dépendances de termes dans les modèles de RI, nous introduisons une condition caractérisant de tels modèle et leur validation théorique. La troisième contribution permet de pallier le problème de disparité des termes en proposant une méthode pour intégrer la similarité entre les termes dans les modèles de RI en s'appuyant sur les représentations distribuées des mots (RDMs). L'idée sous-jacente consiste à permettre aux termes similaires à ceux de la requête de contribuer aux scores des documents. Les extensions des modèles de RI proposées dans le cadre de cette méthode sont validées en utilisant les contraintes heuristiques d'appariement sémantique. La dernière contribution concerne l'amélioration des modèles de rétro-pertinence (Pseudo Relevance Feedback PRF). Étant basée également sur les RDM, notre méthode permet d'intégrer la similarité entre les termes d'expansions et ceux de la requête dans les modèles standards PRF. La validation expérimentale de l'ensemble des contributions apportées dans le cadre de cette thèse est effectuée en utilisant la collection standard TREC 2002/2001 de la langue arabe<br>Given the amount of Arabic textual information available on the web, developing effective Information Retrieval Systems (IRS) has become essential to retrieve relevant information. Most of the current Arabic SRIs are based on the bag-of-words representation, where documents are indexed using surface words, roots or stems. Two main drawbacks of the latter representation are the ambiguity of Single Word Terms (SWTs) and term mismatch.The aim of this work is to deal with SWTs ambiguity and term mismatch. Accordingly, we propose four contributions to improve Arabic content representation, indexing, and retrieval. The first contribution consists of representing Arabic documents using Multi-Word Terms (MWTs). The latter is motivated by the fact that MWTs are more precise representational units and less ambiguous than isolated SWTs. Hence, we propose a hybrid method to extract Arabic MWTs, which combines linguistic and statistical filtering of MWT candidates. The linguistic filter uses POS tagging to identify MWTs candidates that fit a set of syntactic patterns and handles the problem of MWTs variation. Then, the statistical filter rank MWT candidate using our proposed association measure that combines contextual information and both termhood and unithood measures. In the second contribution, we explore and evaluate several IR models for ranking documents using both SWTs and MWTs. Additionally, we investigate a wide range of proximity-based IR models for Arabic IR. Then, we introduce a formal condition that IR models should satisfy to deal adequately with term dependencies. The third contribution consists of a method based on Distributed Representation of Word vectors, namely Word Embedding (WE), for Arabic IR. It relies on incorporating WE semantic similarities into existing probabilistic IR models in order to deal with term mismatch. The aim is to allow distinct, but semantically similar terms to contribute to documents scores. The last contribution is a method to incorporate WE similarity into Pseud-Relevance Feedback PRF for Arabic Information Retrieval. The main idea is to select expansion terms using their distribution in the set of top pseudo-relevant documents along with their similarity to the original query terms. The experimental validation of all the proposed contributions is performed using standard Arabic TREC 2002/2001 collection
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Al-Johar, Badr. "A portable natural language interface from Arabic to SQL." Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/12783/.
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In recent years, natural language interface systems have been built based on the Front End and the Back End architecture which gives a guarantee of modularity and portability to the system as a whole. An Arabic Front End has been built that takes an input sentence, producing syntactic and semantic representations, which it maps into First Order Logic. Expressing the meaning of the user's question in terms of high level world concepts makes the natural language interface independent of the database structure. It is then easier to port the interface Front End to a database for a different domain. The syntactic treatments are based on Generalised Phrase Structure Grammar (GPSG) whereas the semantics are expressed in formal semantics theory. The focus is mainly to provide syntactic and semantic analyses for Arabic queries based on correct Arabic linguistic principles. The proposed treatments are proved and tested by building a prototype system. The prototype is implemented using one of the existing systems called Squirrel. An Arabic morphological analyser is also proposed and implemented to distinguish between two types of morphemes: internal morphemes which are a part of the word's pattern, and external morphemes which are independent words attached to the word but which are not part of the word's pattern. So, the system focuses on the extraction of morphemes from the various inflexions or forms of any Arabic word.
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Matsubara, Shigeki. "Corpus-based Natural Language Processing." INTELLIGENT MEDIA INTEGRATION NAGOYA UNIVERSITY / COE, 2004. http://hdl.handle.net/2237/10355.
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Smith, Sydney. "Approaches to Natural Language Processing." Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/cmc_theses/1817.
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This paper explores topic modeling through the example text of Alice in Wonderland. It explores both singular value decomposition as well as non-‐‑negative matrix factorization as methods for feature extraction. The paper goes on to explore methods for partially supervised implementation of topic modeling through introducing themes. A large portion of the paper also focuses on implementation of these techniques in python as well as visualizations of the results which use a combination of python, html and java script along with the d3 framework. The paper concludes by presenting a mixture of SVD, NMF and partially-‐‑supervised NMF as a possible way to improve topic modeling.
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Al-Nashashibi, May Y. A. "Arabic Language Processing for Text Classification. Contributions to Arabic Root Extraction Techniques, Building An Arabic Corpus, and to Arabic Text Classification Techniques." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/6326.
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The impact and dynamics of Internet-based resources for Arabic-speaking users is increasing in significance, depth and breadth at highest pace than ever, and thus requires updated mechanisms for computational processing of Arabic texts. Arabic is a complex language and as such requires in depth investigation for analysis and improvement of available automatic processing techniques such as root extraction methods or text classification techniques, and for developing text collections that are already labeled, whether with single or multiple labels.
This thesis proposes new ideas and methods to improve available automatic processing techniques for Arabic texts. Any automatic processing technique would require data in order to be used and critically reviewed and assessed, and here an attempt to develop a labeled Arabic corpus is also proposed. This thesis is composed of three parts: 1- Arabic corpus development, 2- proposing, improving and implementing root extraction techniques, and 3- proposing and investigating the effect of different pre-processing methods on single-labeled text classification methods for Arabic.
This thesis first develops an Arabic corpus that is prepared to be used here for testing root extraction methods as well as single-label text classification techniques. It also enhances a rule-based root extraction method by handling irregular cases (that appear in about 34% of texts). It proposes and implements two expanded algorithms as well as an adjustment for a weight-based method. It also includes the algorithm that handles irregular cases to all and compares the performances of these proposed methods with original ones. This thesis thus develops a root extraction system that handles foreign Arabized words by constructing a list of about 7,000 foreign words. The outcome of the technique with best accuracy results in extracting the correct stem and root for respective words in texts, which is an enhanced rule-based method, is used in the third part of this thesis. This thesis finally proposes and implements a variant term frequency inverse document frequency weighting method, and investigates the effect of using different choices of features in document representation on single-label text classification performance (words, stems or roots as well as including to these choices their respective phrases). This thesis applies forty seven classifiers on all proposed representations and compares their performances. One challenge for researchers in Arabic text processing is that reported root extraction techniques in literature are either not accessible or require a long time to be reproduced while labeled benchmark Arabic text corpus is not fully available online. Also, by now few machine learning techniques were investigated on Arabic where usual preprocessing steps before classification were chosen. Such challenges are addressed in this thesis by developing a new labeled Arabic text corpus for extended applications of computational techniques.
Results of investigated issues here show that proposing and implementing an algorithm that handles irregular words in Arabic did improve the performance of all implemented root extraction techniques. The performance of the algorithm that handles such irregular cases is evaluated in terms of accuracy improvement and execution time. Its efficiency is investigated with different document lengths and empirically is found to be linear in time for document lengths less than about 8,000. The rule-based technique is improved the highest among implemented root extraction methods when including the irregular cases handling algorithm. This thesis validates that choosing roots or stems instead of words in documents representations indeed improves single-label classification performance significantly for most used classifiers. However, the effect of extending such representations with their respective phrases on single-label text classification performance shows that it has no significant improvement. Many classifiers were not yet tested for Arabic such as the ripple-down rule classifier. The outcome of comparing the classifiers' performances concludes that the Bayesian network classifier performance is significantly the best in terms of accuracy, training time, and root mean square error values for all proposed and implemented representations.<br>Petra University, Amman (Jordan)
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Al-Nashashibi, May Yacoub Adib. "Arabic language processing for text classification : contributions to Arabic root extraction techniques, building an Arabic corpus, and to Arabic text classification techniques." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/6326.
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The impact and dynamics of Internet-based resources for Arabic-speaking users is increasing in significance, depth and breadth at highest pace than ever, and thus requires updated mechanisms for computational processing of Arabic texts. Arabic is a complex language and as such requires in depth investigation for analysis and improvement of available automatic processing techniques such as root extraction methods or text classification techniques, and for developing text collections that are already labeled, whether with single or multiple labels. This thesis proposes new ideas and methods to improve available automatic processing techniques for Arabic texts. Any automatic processing technique would require data in order to be used and critically reviewed and assessed, and here an attempt to develop a labeled Arabic corpus is also proposed. This thesis is composed of three parts: 1- Arabic corpus development, 2- proposing, improving and implementing root extraction techniques, and 3- proposing and investigating the effect of different pre-processing methods on single-labeled text classification methods for Arabic. This thesis first develops an Arabic corpus that is prepared to be used here for testing root extraction methods as well as single-label text classification techniques. It also enhances a rule-based root extraction method by handling irregular cases (that appear in about 34% of texts). It proposes and implements two expanded algorithms as well as an adjustment for a weight-based method. It also includes the algorithm that handles irregular cases to all and compares the performances of these proposed methods with original ones. This thesis thus develops a root extraction system that handles foreign Arabized words by constructing a list of about 7,000 foreign words. The outcome of the technique with best accuracy results in extracting the correct stem and root for respective words in texts, which is an enhanced rule-based method, is used in the third part of this thesis. This thesis finally proposes and implements a variant term frequency inverse document frequency weighting method, and investigates the effect of using different choices of features in document representation on single-label text classification performance (words, stems or roots as well as including to these choices their respective phrases). This thesis applies forty seven classifiers on all proposed representations and compares their performances. One challenge for researchers in Arabic text processing is that reported root extraction techniques in literature are either not accessible or require a long time to be reproduced while labeled benchmark Arabic text corpus is not fully available online. Also, by now few machine learning techniques were investigated on Arabic where usual preprocessing steps before classification were chosen. Such challenges are addressed in this thesis by developing a new labeled Arabic text corpus for extended applications of computational techniques. Results of investigated issues here show that proposing and implementing an algorithm that handles irregular words in Arabic did improve the performance of all implemented root extraction techniques. The performance of the algorithm that handles such irregular cases is evaluated in terms of accuracy improvement and execution time. Its efficiency is investigated with different document lengths and empirically is found to be linear in time for document lengths less than about 8,000. The rule-based technique is improved the highest among implemented root extraction methods when including the irregular cases handling algorithm. This thesis validates that choosing roots or stems instead of words in documents representations indeed improves single-label classification performance significantly for most used classifiers. However, the effect of extending such representations with their respective phrases on single-label text classification performance shows that it has no significant improvement. Many classifiers were not yet tested for Arabic such as the ripple-down rule classifier. The outcome of comparing the classifiers' performances concludes that the Bayesian network classifier performance is significantly the best in terms of accuracy, training time, and root mean square error values for all proposed and implemented representations.
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Strandberg, Aron, and Patrik Karlström. "Processing Natural Language for the Spotify API : Are sophisticated natural language processing algorithms necessary when processing language in a limited scope?" Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186867.
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Knowing whether you can implement something complex in a simple way in your application is always of interest. A natural language interface is some- thing that could theoretically be implemented in a lot of applications but the complexity of most natural language processing algorithms is a limiting factor. The problem explored in this paper is whether a simpler algorithm that doesn’t make use of convoluted statistical models and machine learning can be good enough. We implemented two algorithms, one utilizing Spotify’s own search and one with a more accurate, o✏ine search. With the best precision we could muster being 81% at an average of 2,28 seconds per query this is not a viable solution for a complete and satisfactory user experience. Further work could push the performance into an acceptable range.
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Chen, Joseph C. H. "Quantum computation and natural language processing." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965581020.
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Knight, Sylvia Frances. "Natural language processing for aerospace documentation." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621395.
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Naphtal, Rachael (Rachael M. ). "Natural language processing based nutritional application." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100640.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 67-68).<br>The ability to accurately and eciently track nutritional intake is a powerful tool in combating obesity and other food related diseases. Currently, many methods used for this task are time consuming or easily abandoned; however, a natural language based application that converts spoken text to nutritional information could be a convenient and eective solution. This thesis describes the creation of an application that translates spoken food diaries into nutritional database entries. It explores dierent methods for solving the problem of converting brands, descriptions and food item names into entries in nutritional databases. Specifically, we constructed a cache of over 4,000 food items, and also created a variety of methods to allow refinement of database mappings. We also explored methods of dealing with ambiguous quantity descriptions and the mapping of spoken quantity values to numerical units. When assessed by 500 users entering their daily meals on Amazon Mechanical Turk, the system was able to map 83.8% of the correctly interpreted spoken food items to relevant nutritional database entries. It was also able to nd a logical quantity for 92.2% of the correct food entries. Overall, this system shows a signicant step towards the intelligent conversion of spoken food diaries to actual nutritional feedback.<br>by Rachael Naphtal.<br>M. Eng.
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Hamrouni, Nadia. "Structure and Processing in Tunisian Arabic: Speech Error Data." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195969.
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This dissertation presents experimental research on speech errors in Tunisian Arabic (TA). The central empirical questions revolve around properties of `exchange errors'. These errors can mis-order lexical, morphological, or sound elements in a variety of patterns. TA's nonconcatenative morphology shows interesting interactions of phrasal and lexical constraints with morphological structure during language production and affords different and revealing error potentials linking the production system with linguistic knowledge.The dissertation studies expand and test generalizations based on Abd-El-Jawad and Abu-Salim's (1987) study of spontaneous speech errors in Jordanian Arabic by experimentally examining apparent regularities in data from real-time language processing perspective. The studies address alternative accounts of error phenomena that have figured prominently in accounts of production processing. Three experiments were designed and conducted based on an error elicitation paradigm used by Ferreira and Humphreys (2001). Experiment 1 tested within-phrase exchange errors focused on root versus non-root exchanges and lexical versus non-lexical outcomes for root and non-root errors. Experiments 2 and 3 addressed between-phrase exchange errors focused on violations of the Grammatical Category Constraint (GCC).The study of exchange potentials for the within-phrase items (experiment 1) contrasted lexical and non-lexical outcomes. The expectation was that these would include a significant number of root exchanges and that the lexical status of the resulting forms would not preclude error. Results show that root and vocalic pattern exchanges were very rare and that word forms rather than root forms were the dominant influence in the experimental performance. On the other hand, the study of exchange errors across phrasal boundaries of items that do or do not correspond in grammatical category (experiments 2 and 3) pursued two principal questions, one concerning the error rate and the second concerning the error elements. The expectation was that the errors predominantly come from grammatical category matches. That outcome would reinforce the interpretation that processing operations reflect the assignment of syntactically labeled elements to their location in phrasal structures. Results corroborated with the expectation. However, exchange errors involving words of different grammatical categories were also frequent. This has implications for speech monitoring models and the automaticity of the GCC.
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Eriksson, Simon. "COMPARING NATURAL LANGUAGE PROCESSING TO STRUCTURED QUERY LANGUAGE ALGORITHMS." Thesis, Umeå universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-163310.
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Using natural language processing to create Structured Query Language (SQL) queries has many benefits in theory. Even though SQL is an expressive and powerful language it requires certain technical knowledge to use. An interface effectively utilizing natural language processing would instead allow the user to communicate with the SQL database as if they were communicating with another human being. In this paper I compare how two of the currently most advanced open source algorithms (TypeSQL and SyntaxSQL) in this field can understandadvanced SQL. I show that SyntaxSQL is signicantly more accurate but makes some sacrices in execution time compared to TypeSQL.
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Pham, Son Bao Computer Science & Engineering Faculty of Engineering UNSW. "Incremental knowledge acquisition for natural language processing." Awarded by:University of New South Wales. School of Computer Science and Engineering, 2006. http://handle.unsw.edu.au/1959.4/26299.
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Linguistic patterns have been used widely in shallow methods to develop numerous NLP applications. Approaches for acquiring linguistic patterns can be broadly categorised into three groups: supervised learning, unsupervised learning and manual methods. In supervised learning approaches, a large annotated training corpus is required for the learning algorithms to achieve decent results. However, annotated corpora are expensive to obtain and usually available only for established tasks. Unsupervised learning approaches usually start with a few seed examples and gather some statistics based on a large unannotated corpus to detect new examples that are similar to the seed ones. Most of these approaches either populate lexicons for predefined patterns or learn new patterns for extracting general factual information; hence they are applicable to only a limited number of tasks. Manually creating linguistic patterns has the advantage of utilising an expert's knowledge to overcome the scarcity of annotated data. In tasks with no annotated data available, the manual way seems to be the only choice. One typical problem that occurs with manual approaches is that the combination of multiple patterns, possibly being used at different stages of processing, often causes unintended side effects. Existing approaches, however, do not focus on the practical problem of acquiring those patterns but rather on how to use linguistic patterns for processing text. A systematic way to support the process of manually acquiring linguistic patterns in an efficient manner is long overdue. This thesis presents KAFTIE, an incremental knowledge acquisition framework that strongly supports experts in creating linguistic patterns manually for various NLP tasks. KAFTIE addresses difficulties in manually constructing knowledge bases of linguistic patterns, or rules in general, often faced in existing approaches by: (1) offering a systematic way to create new patterns while ensuring they are consistent; (2) alleviating the difficulty in choosing the right level of generality when creating a new pattern; (3) suggesting how existing patterns can be modified to improve the knowledge base's performance; (4) making the effort in creating a new pattern, or modifying an existing pattern, independent of the knowledge base's size. KAFTIE, therefore, makes it possible for experts to efficiently build large knowledge bases for complex tasks. This thesis also presents the KAFDIS framework for discourse processing using new representation formalisms: the level-of-detail tree and the discourse structure graph.
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張少能 and Siu-nang Bruce Cheung. "A concise framework of natural language processing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31208563.
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Cahill, Lynne Julie. "Syllable-based morphology for natural language processing." Thesis, University of Sussex, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386529.
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This thesis addresses the problem of accounting for morphological alternation within Natural Language Processing. It proposes an approach to morphology which is based on phonological concepts, in particular the syllable, in contrast to morpheme-based approaches which have standardly been used by both NLP and linguistics. It is argued that morpheme-based approaches, within both linguistics and NLP, grew out of the apparently purely affixational morphology of European languages, and especially English, but are less appropriate for non-affixational languages such as Arabic. Indeed, it is claimed that even accounts of those European languages miss important linguistic generalizations by ignoring more phonologically based alternations, such as umlaut in German and ablaut in English. To justify this approach, we present a wide range of data from languages as diverse as German and Rotuman. A formal language, MOLUSe, is described, which allows for the definition of declarative mappings between syllable-sequences, and accounts of non-trivial fragments of the inflectional morphology of English, Arabic and Sanskrit are presented, to demonstrate the capabilities of the language. A semantics for the language is defined, and the implementation of an interpreter is described. The thesis discusses theoretical (linguistic) issues, as well as implementational issues involved in the incorporation of MOLUSC into a larger lexicon system. The approach is contrasted with previous work in computational morphology, in particular finite-state morphology, and its relation to other work in the fields of morphology and phonology is also discussed.
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Cheung, Siu-nang Bruce. "A concise framework of natural language processing /." [Hong Kong : University of Hong Kong], 1989. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12432544.
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Hu, Jin. "Explainable Deep Learning for Natural Language Processing." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254886.
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Deep learning methods get impressive performance in many Natural Neural Processing (NLP) tasks, but it is still difficult to know what happened inside a deep neural network. In this thesis, a general overview of Explainable AI and how explainable deep learning methods applied for NLP tasks is given. Then the Bi-directional LSTM and CRF (BiLSTM-CRF) model for Named Entity Recognition (NER) task is introduced, as well as the approach to make this model explainable. The approach to visualize the importance of neurons in Bi-LSTM layer of the model for NER by Layer-wise Relevance Propagation (LRP) is proposed, which can measure how neurons contribute to each predictionof a word in a sequence. Ideas about how to measure the influence of CRF layer of the Bi-LSTM-CRF model is also described.<br>Djupa inlärningsmetoder får imponerande prestanda i många naturliga Neural Processing (NLP) uppgifter, men det är fortfarande svårt att veta vad hände inne i ett djupt neuralt nätverk. I denna avhandling, en allmän översikt av förklarliga AI och hur förklarliga djupa inlärningsmetoder tillämpas för NLP-uppgifter ges. Då den bi-riktiga LSTM och CRF (BiLSTM-CRF) modell för Named Entity Recognition (NER) uppgift införs, liksom tillvägagångssättet för att göra denna modell förklarlig. De tillvägagångssätt för att visualisera vikten av neuroner i BiLSTM-skiktet av Modellen för NER genom Layer-Wise Relevance Propagation (LRP) föreslås, som kan mäta hur neuroner bidrar till varje förutsägelse av ett ord i en sekvens. Idéer om hur man mäter påverkan av CRF-skiktet i Bi-LSTM-CRF-modellen beskrivs också.
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Lei, Tao Ph D. Massachusetts Institute of Technology. "Interpretable neural models for natural language processing." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108990.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 109-119).<br>The success of neural network models often comes at a cost of interpretability. This thesis addresses the problem by providing justifications behind the model's structure and predictions. In the first part of this thesis, we present a class of sequence operations for text processing. The proposed component generalizes from convolution operations and gated aggregations. As justifications, we relate this component to string kernels, i.e. functions measuring the similarity between sequences, and demonstrate how it encodes the efficient kernel computing algorithm into its structure. The proposed model achieves state-of-the-art or competitive results compared to alternative architectures (such as LSTMs and CNNs) across several NLP applications. In the second part, we learn rationales behind the model's prediction by extracting input pieces as supporting evidence. Rationales are tailored to be short and coherent, yet sufficient for making the same prediction. Our approach combines two modular components, generator and encoder, which are trained to operate well together. The generator specifies a distribution over text fragments as candidate rationales and these are passed through the encoder for prediction. Rationales are never given during training. Instead, the model is regularized by the desiderata for rationales. We demonstrate the effectiveness of this learning framework in applications such multi-aspect sentiment analysis. Our method achieves a performance over 90% evaluated against manual annotated rationales.<br>by Tao Lei.<br>Ph. D.
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Grinman, Alex J. "Natural language processing on encrypted patient data." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/113438.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 85-86).<br>While many industries can benefit from machine learning techniques for data analysis, they often do not have the technical expertise nor computational power to do so. Therefore, many organizations would benefit from outsourcing their data analysis. Yet, stringent data privacy policies prevent outsourcing sensitive data and may stop the delegation of data analysis in its tracks. In this thesis, we put forth a two-party system where one party capable of powerful computation can run certain machine learning algorithms from the natural language processing domain on the second party's data, where the first party is limited to learning only specific functions of the second party's data and nothing else. Our system provides simple cryptographic schemes for locating keywords, matching approximate regular expressions, and computing frequency analysis on encrypted data. We present a full implementation of this system in the form of a extendible software library and a command line interface. Finally, we discuss a medical case study where we used our system to run a suite of unmodified machine learning algorithms on encrypted free text patient notes.<br>by Alex J. Grinman.<br>M. Eng.
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Alharthi, Haifa. "Natural Language Processing for Book Recommender Systems." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39134.
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The act of reading has benefits for individuals and societies, yet studies show that reading declines, especially among the young. Recommender systems (RSs) can help stop such decline. There is a lot of research regarding literary books using natural language processing (NLP) methods, but the analysis of textual book content to improve recommendations is relatively rare. We propose content-based recommender systems that extract elements learned from book texts to predict readers’ future interests. One factor that influences reading preferences is writing style; we propose a system that recommends books after learning their authors’ writing style. To our knowledge, this is the first work that transfers the information learned by an author-identification model to a book RS. Another approach that we propose uses over a hundred lexical, syntactic, stylometric, and fiction-based features that might play a role in generating high-quality book recommendations. Previous book RSs include very few stylometric features; hence, our study is the first to include and analyze a wide variety of textual elements for book recommendations. We evaluated both approaches according to a top-k recommendation scenario. They give better accuracy when compared with state-of-the-art content and collaborative filtering methods. We highlight the significant factors that contributed to the accuracy of the recommendations using a forest of randomized regression trees. We also conducted a qualitative analysis by checking if similar books/authors were annotated similarly by experts.
Our content-based systems suffer from the new user problem, well-known in the field of RSs, that hinders their ability to make accurate recommendations. Therefore, we propose a Topic Model-Based book recommendation component (TMB) that addresses the issue by using the topics learned from a user’s shared text on social media, to recognize their interests and map them to related books. To our knowledge, there is no literature regarding book RSs that exploits public social networks other than book-cataloging websites. Using topic modeling techniques, extracting user interests can be automatic and dynamic, without the need to search for predefined concepts. Though TMB is designed to complement other systems, we evaluated it against a traditional book CB. We assessed the top k recommendations made by TMB and CB and found that both retrieved a comparable number of books, even though CB relied on users’ rating history, while TMB only required their social profiles.
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Medlock, Benjamin William. "Investigating classification for natural language processing tasks." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611949.
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Woldemariam, Yonas Demeke. "Natural language processing in cross-media analysis." Licentiate thesis, Umeå universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-147640.
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A cross-media analysis framework is an integrated multi-modal platform where a media resource containing different types of data such as text, images, audio and video is analyzed with metadata extractors, working jointly to contextualize the media resource. It generally provides cross-media analysis and automatic annotation, metadata publication and storage, searches and recommendation services. For on-line content providers, such services allow them to semantically enhance a media resource with the extracted metadata representing the hidden meanings and make it more efficiently searchable. Within the architecture of such frameworks, Natural Language Processing (NLP) infrastructures cover a substantial part. The NLP infrastructures include text analysis components such as a parser, named entity extraction and linking, sentiment analysis and automatic speech recognition. Since NLP tools and techniques are originally designed to operate in isolation, integrating them in cross-media frameworks and analyzing textual data extracted from multimedia sources is very challenging. Especially, the text extracted from audio-visual content lack linguistic features that potentially provide important clues for text analysis components. Thus, there is a need to develop various techniques to meet the requirements and design principles of the frameworks. In our thesis, we explore developing various methods and models satisfying text and speech analysis requirements posed by cross-media analysis frameworks. The developed methods allow the frameworks to extract linguistic knowledge of various types and predict various information such as sentiment and competence. We also attempt to enhance the multilingualism of the frameworks by designing an analysis pipeline that includes speech recognition, transliteration and named entity recognition for Amharic, that also enables the accessibility of Amharic contents on the web more efficiently. The method can potentially be extended to support other under-resourced languages.
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Miao, Yishu. "Deep generative models for natural language processing." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:e4e1f1f9-e507-4754-a0ab-0246f1e1e258.
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Deep generative models are essential to Natural Language Processing (NLP) due to their outstanding ability to use unlabelled data, to incorporate abundant linguistic features, and to learn interpretable dependencies among data. As the structure becomes deeper and more complex, having an effective and efficient inference method becomes increasingly important. In this thesis, neural variational inference is applied to carry out inference for deep generative models. While traditional variational methods derive an analytic approximation for the intractable distributions over latent variables, here we construct an inference network conditioned on the discrete text input to provide the variational distribution. The powerful neural networks are able to approximate complicated non-linear distributions and grant the possibilities for more interesting and complicated generative models. Therefore, we develop the potential of neural variational inference and apply it to a variety of models for NLP with continuous or discrete latent variables. This thesis is divided into three parts. Part I introduces a <b>generic variational inference framework</b> for generative and conditional models of text. For continuous or discrete latent variables, we apply a continuous reparameterisation trick or the REINFORCE algorithm to build low-variance gradient estimators. To further explore Bayesian non-parametrics in deep neural networks, we propose a family of neural networks that parameterise categorical distributions with continuous latent variables. Using the stick-breaking construction, an unbounded categorical distribution is incorporated into our deep generative models which can be optimised by stochastic gradient back-propagation with a continuous reparameterisation. Part II explores <b>continuous latent variable models for NLP</b>. Chapter 3 discusses the Neural Variational Document Model (NVDM): an unsupervised generative model of text which aims to extract a continuous semantic latent variable for each document. In Chapter 4, the neural topic models modify the neural document models by parameterising categorical distributions with continuous latent variables, where the topics are explicitly modelled by discrete latent variables. The models are further extended to neural unbounded topic models with the help of stick-breaking construction, and a truncation-free variational inference method is proposed based on a Recurrent Stick-breaking construction (RSB). Chapter 5 describes the Neural Answer Selection Model (NASM) for learning a latent stochastic attention mechanism to model the semantics of question-answer pairs and predict their relatedness. Part III discusses <b>discrete latent variable models</b>. Chapter 6 introduces latent sentence compression models. The Auto-encoding Sentence Compression Model (ASC), as a discrete variational auto-encoder, generates a sentence by a sequence of discrete latent variables representing explicit words. The Forced Attention Sentence Compression Model (FSC) incorporates a combined pointer network biased towards the usage of words from source sentence, which significantly improves the performance when jointly trained with the ASC model in a semi-supervised learning fashion. Chapter 7 describes the Latent Intention Dialogue Models (LIDM) that employ a discrete latent variable to learn underlying dialogue intentions. Additionally, the latent intentions can be interpreted as actions guiding the generation of machine responses, which could be further refined autonomously by reinforcement learning. Finally, Chapter 8 summarizes our findings and directions for future work.
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Kesarwani, Vaibhav. "Automatic Poetry Classification Using Natural Language Processing." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37309.
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Poetry, as a special form of literature, is crucial for computational linguistics. It has a high density of emotions, figures of speech, vividness, creativity, and ambiguity. Poetry poses a much greater challenge for the application of Natural Language Processing algorithms than any other literary genre.
Our system establishes a computational model that classifies poems based on similarity features like rhyme, diction, and metaphor.
For rhyme analysis, we investigate the methods used to classify poems based on rhyme patterns. First, the overview of different types of rhymes is given along with the detailed description of detecting rhyme type and sub-types by the application of a pronunciation dictionary on our poetry dataset. We achieve an accuracy of 96.51% in identifying rhymes in poetry by applying a phonetic similarity model. Then we achieve a rhyme quantification metric RhymeScore based on the matching phonetic transcription of each poem. We also develop an application for the visualization of this quantified RhymeScore as a scatter plot in 2 or 3 dimensions.
For diction analysis, we investigate the methods used to classify poems based on diction. First the linguistic quantitative and semantic features that constitute diction are enumerated. Then we investigate the methodology used to compute these features from our poetry dataset. We also build a word embeddings model on our poetry dataset with 1.5 million words in 100 dimensions and do a comparative analysis with GloVe embeddings.
Metaphor is a part of diction, but as it is a very complex topic in its own right, we address it as a stand-alone issue and develop several methods for it. Previous work on metaphor detection relies on either rule-based or statistical models, none of them applied to poetry. Our methods focus on metaphor detection in a poetry corpus, but we test on non-poetry data as well. We combine rule-based and statistical models (word embeddings) to develop a new classification system. Our first metaphor detection method achieves a precision of 0.759 and a recall of 0.804 in identifying one type of metaphor in poetry, by using a Support Vector Machine classifier with various types of features. Furthermore, our deep learning model based on a Convolutional Neural Network achieves a precision of 0.831 and a recall of 0.836 for the same task. We also develop an application for generic metaphor detection in any type of natural text.
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Huang, Yin Jou. "Event Centric Approaches in Natural Language Processing." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/265210.
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Bakheet, Mohammed. "Improving Speech Recognition for Arabic language Using Low Amounts of Labeled Data." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176437.
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The importance of Automatic Speech Recognition (ASR) Systems, whose job is to generate text from audio, is increasing as the number of applications of these systems is rapidly going up. However, when it comes to training ASR systems, the process is difficult and rather tedious, and that could be attributed to the lack of training data. ASRs require huge amounts of annotated training data containing the audio files and the corresponding accurately written transcript files. This annotated (labeled) training data is very difficult to find for most of the languages, it usually requires people to perform the annotation manually which, apart from the monetary price it costs, is error-prone. A supervised training task is impractical for this scenario. The Arabic language is one of the languages that do not have an abundance of labeled data, which makes its ASR system's accuracy very low compared to other resource-rich languages such as English, French, or Spanish. In this research, we take advantage of unlabeled voice data by learning general data representations from unlabeled training data (only audio files) in a self-supervised task or pre-training phase. This phase is done by using wav2vec 2.0 framework which masks out input in the latent space and solves a contrastive task. The model is then fine-tuned on a few amounts of labeled data. We also exploit models that have been pre-trained on different languages, by using wav2vec 2.0, for the purpose of fine-tuning them on Arabic language by using annotated Arabic data. We show that using wav2vec 2.0 framework for pre-training on Arabic is considerably time and resource-consuming. It took the model 21.5 days (about 3 weeks) to complete 662 epochs and get a validation accuracy of 58%. Arabic is a right-to-left (rtl) language with many diacritics that indicate how letters should be pronounced, these two features make it difficult for Arabic to fit into these models, as it requires heavy pre-processing for the transcript files. We demonstrate that we can fine-tune a cross-lingual model, that is trained on raw waveforms of speech in multiple languages, on Arabic data and get a low word error rate 36.53%. We also prove that by fine-tuning the model parameters we can increase the accuracy, thus, decrease the word error rate from 54.00% to 36.69%.
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Guy, Alison. "Logical expressions in natural language conditionals." Thesis, University of Sunderland, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278644.
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Walker, Alden. "Natural language interaction with robots." Diss., Connect to the thesis, 2007. http://hdl.handle.net/10066/1275.
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Fuchs, Gil Emanuel. "Practical natural language processing question answering using graphs /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2004. http://uclibs.org/PID/11984.
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Kolak, Okan. "Rapid resource transfer for multilingual natural language processing." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3182.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.<br>Thesis research directed by: Dept. of Linguistics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Bigert, Johnny. "Automatic and unsupervised methods in natural language processing." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156.
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Cohn, Trevor A. "Scaling conditional random fields for natural language processing /." Connect to thesis, 2007. http://eprints.unimelb.edu.au/archive/00002874.
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Zhang, Lidan, and 张丽丹. "Exploiting linguistic knowledge for statistical natural language processing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46506299.
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Grubbs, Elmer Andrew. "An information theoretic approach to natural language processing." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186886.
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A new method of natural language processing, based on the theory of information is described. Parsing of a sentence is accomplished not in a sequential manner, but in a fashion that begins by searching for the main verb of the sentence, then for the object, subject and perhaps for a prepositional phrase. As each new part of speech is located, the uncertainty of the sentence's meaning is reduced. When the uncertainty reaches zero, the parsing is complete, and the machine performs the task assigned by the input sentence. The process is modeled by a Markov Chain, which can often be used for the internal representation of the sentence. All of this work is done for communication with an intelligent task oriented machine, but the theoretical basis for extending this to other, more complicated domains is also described. A description of a methodology for extending the theory, so that it can be used for the implementation of a machine that learns is also described in this paper. By using belief networks, the machine constructs additions to its basic Markov Chain in order to handle new verbs and objects, which were not included in the original programming. Once implemented, the system will then treat the new word as if it had originally been programmed into the machine. Finally, several prototypes are described which have been written to validate the theory presented. The information theoretic system contained herein is compared to other techniques of natural language processing, and shown to have significant advantages.
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Cosh, Kenneth John. "Supporting organisational semiotics with natural language processing techniques." Thesis, Lancaster University, 2003. http://eprints.lancs.ac.uk/12351/.
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Allott, Nicholas Mark. "A natural language processing framework for automated assessment." Thesis, Nottingham Trent University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314333.
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Fass, D. "Collative semantics : A semantics for natural language processing." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383507.
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Djoweini, Camran, and Henrietta Hellberg. "Approaches to natural language processing in app development." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230167.
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Natural language processing is an on-going field that is not yet fully established. A high demand for natural language processing in applications creates a need for good development-tools and different implementation approaches developed to suit the engineers behind the applications. This project approaches the field from an engineering point of view to research approaches, tools, and techniques that are readily available today for development of natural language processing support. The sub-area of information retrieval of natural language processing was examined through a case study, where prototypes were developed to get a deeper understanding of the tools and techniques used for such tasks from an engineering point of view. We found that there are two major approaches to developing natural language processing support for applications, high-level and low-level approaches. A categorization of tools and frameworks belonging to the two approaches as well as the source code, documentation and, evaluations, of two prototypes developed as part of the research are presented. The choice of approach, tools and techniques should be based on the specifications and requirements of the final product and both levels have their own pros and cons. The results of the report are, to a large extent, generalizable as many different natural language processing tasks can be solved using similar solutions even if their goals vary.<br>Datalingvistik (engelska natural language processing) är ett område inom datavetenskap som ännu inte är fullt etablerat. En hög efterfrågan av stöd för naturligt språk i applikationer skapar ett behov av tillvägagångssätt och verktyg anpassade för ingenjörer. Detta projekt närmar sig området från en ingenjörs synvinkel för att undersöka de tillvägagångssätt, verktyg och tekniker som finns tillgängliga att arbeta med för utveckling av stöd för naturligt språk i applikationer i dagsläget. Delområdet ‘information retrieval’ undersöktes genom en fallstudie, där prototyper utvecklades för att skapa en djupare förståelse av verktygen och teknikerna som används inom området. Vi kom fram till att det går att kategorisera verktyg och tekniker i två olika grupper, beroende på hur distanserad utvecklaren är från den underliggande bearbetningen av språket. Kategorisering av verktyg och tekniker samt källkod, dokumentering och utvärdering av prototyperna presenteras som resultat. Valet av tillvägagångssätt, tekniker och verktyg bör baseras på krav och specifikationer för den färdiga produkten. Resultaten av studien är till stor del generaliserbara eftersom lösningar till många problem inom området är likartade även om de slutgiltiga målen skiljer sig åt.