检索结果-内蒙古大学图书馆

2008 Conference on Empirical methods in natural language processing, EMNLP 2008, Co-located with AMTA 2008 and the International workshop on Spoken language Translation

作者： Shen, Libin Joshi, Aravind K. BBN Technologies United States University of Pennsylvania United States

In this paper, we first introduce a new architecture for parsing, bidirectional incremental parsing. We propose a novel algorithm for incremental construction, which can be applied to many structure learning problems in NLP. We apply this algorithm to LTAG dependency parsing, and achieve significant improvement on accuracy over the previous best result on the same data set. © 2008 Association for Computational Linguistics.

关键词： natural language processing systems

来源：评论

学校读者我要写书评

暂无评论

Learning the scope of negation in biomedical texts

Learning the scope of negation in biomedical texts

引用

2008 Conference on Empirical methods in natural language processing, EMNLP 2008, Co-located with AMTA 2008 and the International workshop on Spoken language Translation

作者： Morante, Roser Liekens, Anthony Daelemans, Walter CNTS-Language Technology Group University of Antwerp Prinsstraat 13 B-2000 Antwerpen Belgium Applied Molecular Genomics Group University of Antwerp Prinsstraat 13 B-2000 Antwerpen Belgium

In this paper we present a machine learning system that finds the scope of negation in biomedical texts. The system consists of two memory-based engines, one that decides if the tokens in a sentence are negation signals, and another that finds the full scope of these negation signals. Our approach to negation detection differs in two main aspects from existing research on negation. first, we focus on finding the scope of negation signals, instead of determining whether a term is negated or not. Second, we apply supervised machine learning techniques, whereas most existing systems apply rule-based algorithms. As far as we know, this way of approaching the negation scope finding task is novel. © 2008 Association for Computational Linguistics.

关键词： Supervised learning

来源：评论

学校读者我要写书评

暂无评论

Online large-margin training of syntactic and structural translation features

Online large-margin training of syntactic and structural tra...

引用

2008 Conference on Empirical methods in natural language processing, EMNLP 2008, Co-located with AMTA 2008 and the International workshop on Spoken language Translation

作者： Chiang, David Marton, Yuval Resnik, Philip Information Sciences Institute University of Southern California 4676 Admiralty Way Marina del Rey CA 90292 United States Department of Linguistics Laboratory for Computational Linguistics and Information Processing University of Maryland College Park MD 20742 United States

Minimum-error-rate training (MERT) is a bottleneck for current development in statistical machine translation because it is limited in the number of weights it can reliably optimize. Building on the work of Watanabe et al., we explore the use of the MIRA algorithm of Crammer et al. as an alternative to MERT. We first show that by parallel processing and exploiting more of the parse forest, we can obtain results using MIRA that match or surpass MERT in terms of both translation quality and computational cost. We then test the method on two classes of features that address deficiencies in the Hiero hierarchical phrase-based model: first, we simultaneously train a large number of Marton and Resnik's soft syntactic constraints, and, second, we introduce a novel structural distortion model. In both cases we obtain significant improvements in translation performance. Optimizing them in combination, for a total of 56 feature weights, we improve performance by 2.6 BLEU on a subset of the NIST 2006 Arabic-English evaluation data. © 2008 Association for Computational Linguistics.

关键词： Syntactics

来源：评论

学校读者我要写书评

暂无评论

UNIGE experiments on robust word sense disambiguation

UNIGE experiments on robust word sense disambiguation

引用

2008 Working Notes for CLEF workshop, CLEF 2008 - Co-located with the 12th European Conference on Digital Libraries, ECDL 2008

作者： Guyot, Jacques Falquet, Gilles Radhouani, Saïd Benzineb, Karim Centre Universitaire d'Informatique University of Geneva Route de Drize 7 Carouge1227 Switzerland

This task was meant to compare the results of two different retrieval techniques: the first one was based on the words found in documents and query texts;the second one was based on the senses (concepts) obtained by disambiguating the words in documents and queries. The underlying goal was to come up with a more precise knowledge about the possible improvements brought by word sense disambiguation (WSD) in the information retrieval process. The proposed task structure was interesting in that it drew up a clear separation between the actors (humans or computers): those who provide the corpus, those who disambiguate it, and those who query it. Thus it was possible to test the universality and the interoperability of the methods and algorithms involved.

关键词： natural language processing systems

来源：评论

学校读者我要写书评

暂无评论

Programming spatial algorithms in natural language

Programming spatial algorithms in natural language

引用

2008 AAAI workshop

作者： Galitsky, Boris Usikov, Daniel Knowledge-Trail Inc. 9 Charles Str. Natick MA 01760 United States Electroglas Inc. 5729 Fontanoso Way San Jose CA 95138 United States

ISBN: (纸本)9781577353799

We attempt programming spatial algorithms in natural language. The input of the proposed system is a natural language description of a spatial processing algorithm, and the output is the object-oriented program code to be compiled and executed. Two approaches are proposed and evaluated: the first one is based on textual pattern matching: the best fit pattern is selected for each sentence, and objects and methods are instantiated according to this textual pattern. The second one converts text into logic forms subject to a number of transformations to derive resultant code. A number of heuristic rules are built to perform these transformations at every step. Additional pass is then required to process sentences' coreferences to find identical objects, methods and variables between code statements. The result of this preliminary research suggest that the using the system for programming in natural language in the interactive mode, where a user manually edits the generated code, is a way to noticeably increase coding performance. However, at this time, an accuracy of a fully automated (i.e. non-interactive) code generation mode is still too low to be usable. Copyright © 2008, Association for the Advancement of Artificial Intelligence.

关键词： Pattern matching

来源：评论

学校读者我要写书评

暂无评论

Word sense disambiguation using OntoNotes: An empirical study

Word sense disambiguation using OntoNotes: An empirical stud...

引用

2008 Conference on Empirical methods in natural language processing, EMNLP 2008, Co-located with AMTA 2008 and the International workshop on Spoken language Translation

作者： Zhong, Zhi Ng, Hwee Tou Chan, Yee Seng Department of Computer Science National University of Singapore Law Link Singapore 117590 Singapore

The accuracy of current word sense disambiguation (WSD) systems is affected by the fine-grained sense inventory of WordNet as well as a lack of training examples. Using the WSD examples provided through OntoNotes, we conduct the first large-scale WSD evaluation involving hundreds of word types and tens of thousands of sense-tagged examples, while adopting a coarse-grained sense inventory. We show that though WSD systems trained with a large number of examples can obtain a high level of accuracy, they nevertheless suffer a substantial drop in accuracy when applied to a different domain. To address this issue, we propose combining a domain adaptation technique using feature augmentation with active learning. Our results show that this approach is effective in reducing the annotation effort required to adapt a WSD system to a new domain. Finally, we propose that one can maximize the dual benefits of reducing the annotation effort while ensuring an increase in WSD accuracy, by only performing active learning on the set of most frequently occurring word types. © 2008 Association for Computational Linguistics.

关键词： natural language processing systems

来源：评论

学校读者我要写书评

暂无评论

The linguistic structure of English web-search queries

The linguistic structure of English web-search queries

引用

2008 Conference on Empirical methods in natural language processing, EMNLP 2008, Co-located with AMTA 2008 and the International workshop on Spoken language Translation

作者： Barr, Cory Jones, Rosie Regelson, Moira Yahoo Inc. 701 First Ave. Sunnyvale CA 94089 United States Perfect Market Inc. Pasadena CA 91103 United States

Web-search queries are known to be short, but little else is known about their structure. In this paper we investigate the applicability of part-of-speech tagging to typical English-language web search-engine queries and the potential value of these tags for improving search results. We begin by identifying a set of part-of-speech tags suitable for search queries and quantifying their occurrence. We find that proper-nouns constitute 40% of query terms, and proper nouns and nouns together constitute over 70% of query terms. We also show that the majority of queries are noun-phrases, not unstructured collections of terms. We then use a set of queries manually labeled with these tags to train a Brill tag-ger and evaluate its performance. In addition, we investigate classification of search queries into grammatical classes based on the syntax of part-of-speech tag sequences. We also conduct preliminary investigative experiments into the practical applicability of leveraging query-trained part-of-speech taggers for information-retrieval tasks. In particular, we show that part-of-speech information can be a significant feature in machine-learned search-result relevance. These experiments also include the potential use of the tagger in selecting words for omission or substitution in query reformulation, actions which can improve recall. We conclude that training a part-of-speech tagger on labeled corpora of queries significantly outperforms taggers based on traditional corpora, and leveraging the unique linguistic structure of web-search queries can improve search experience. © 2008 Association for Computational Linguistics.

关键词： Search engines

来源：评论

学校读者我要写书评

暂无评论

PuReD-MCL: a graph-based PubMed document clustering methodology

引用

BIOINFORMATICS 2008年第17期24卷 1935-1941页

作者： Theodosiou, T. Darzentas, N. Angelis, L. Ouzounis, C. A. Aristotle Univ Thessaloniki Dept Informat GR-54006 Thessaloniki Greece Ctr Res & Technol Hellas CERTH Inst Agrobiotechnol Computat Genom Unit GR-57001 Thessaloniki Greece Kings Coll London Sch Phys Sci & Engn Ctr Bioinformat London WC2R 2LS England

Motivation: Biomedical literature is the principal repository of biomedical knowledge, with PubMed being the most complete database collecting, organizing and analyzing such textual knowledge. There are numerous efforts that attempt to exploit this information by using text mining and machine learning techniques. We developed a novel approach, called PuReD-MCL (Pubmed Related Documents-MCL), which is based on the graph clustering algorithm MCL and relevant resources from PubMed. methods: PuReD-MCL avoids using natural language processing (NLP) techniques directly;instead, it takes advantage of existing resources, available from PubMed. PuReD-MCL then clusters documents efficiently using the MCL graph clustering algorithm, which is based on graph flow simulation. This process allows users to analyse the results by highlighting important clues, and finally to visualize the clusters and all relevant information using an interactive graph layout algorithm, for instance BioLayout Express 3D. Results: The methodology was applied to two different datasets, previously used for the validation of the document clustering tool TextQuest. The first dataset involves the organisms Escherichia coli and yeast, whereas the second is related to Drosophila development. PuReD-MCL successfully reproduces the annotated results obtained from TextQuest, while at the same time provides additional insights into the clusters and the corresponding documents.

关键词： Algorithms Artificial Intelligence Cluster Analysis Database Management Systems Information Storage and Retrieval/methods natural language processing Pattern Recognition, Automated/methods PubMed Software

来源：评论

学校读者我要写书评

暂无评论

An evaluation understudy for dialogue coherence models 9

An evaluation understudy for dialogue coherence models

引用

9th SIGdial workshop on Discourse and Dialogue

作者： Gandhe, Sudeep Traum, David Institute for Creative Technologies University of Southern California 13274 Fiji way Marina del Rey CA 90292 United States

ISBN: (纸本)9781932432176

Evaluating a dialogue system is seen as a major challenge within the dialogue research community. Due to the very nature of the task, most of the evaluation methods need a substantial amount of human involvement. Following the tradition in machine translation, summarization and discourse coherence modeling, we introduce the the idea of evaluation understudy for dialogue coherence models. Following (Lapata, 2006), we use the information ordering task as a testbed for evaluating dialogue coherence models. This paper reports findings about the reliability of the information ordering task as applied to dialogues. We find that simple n-gram co-occurrence statistics similar in spirit to BLEU (Papineni et al., 2001) correlate very well with human judgments for dialogue coherence. © 2008 Association for Computational Linguistics.

关键词： Speech processing

来源：评论

学校读者我要写书评

暂无评论

Large-scale directional relationship extraction and resolution

引用

BMC BIOINFORMATICS 2008年第Sup9期9卷 1-13页

作者： Giles, Cory B. Wren, Jonathan D. Oklahoma Med Res Fdn Arthritis & Immunol Res Program Oklahoma City OK 73104 USA

Background: Relationships between entities such as genes, chemicals, metabolites, phenotypes and diseases in MEDLINE are often directional. That is, one may affect the other in a positive or negative manner. Detection of causality and direction is key in piecing pathways together and in examining possible implications of experimental results. Because of the size and growth of biomedical literature, it is increasingly important to be able to automate this process as much as possible. Results: Here we present a method of relation extraction using dependency graph parsing with SVM classification. We tested the SVM classifier first on gold standard corpora from GENIA and find it achieved 82% precision and 94.8% recall (F-measure of 87.9) on these standardized test sets. We then applied the entire system to all available MEDLINE abstracts for two target interactions with known effects. We find that while some directional relations are extracted with low ambiguity, others are apparently contradictory, at least when considered in an isolated context. When examined, it is apparent some are dependent upon the surrounding context (e. g. whether the relationship referred to short-term or long-term effects, or whether the focus was extracellular versus intracellular). Conclusion: Thesaurus-based directional relation extraction can be done with reasonable accuracy, but is prone to false-positives on larger corpora due to noun modifiers. Furthermore, methods of resolving or disambiguating relationship context and contingencies are important for large-scale corpora.

关键词： Support Vector Machine Caffeine natural language processing Dependency Path Query Term

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：