Results 1 - 10 of 1,093

Named Entity Recognition without Gazetteers

by Andrei Mikheev, Marc Moens, Claire Grover , 1999
"... It is often claimed that Named Entity recognition systems need extensive gazetteers--lists of names of people, organisations, locations, and other named entities. Indeed, the compilation of such gazetteers is sometimes mentioned as a bottleneck in the design of Named Entity recognition systems. We r ..."
Abstract - Cited by 168 (6 self) - Add to MetaCart
report on a Named Entity recognition system which combines rule-based grammars with statistical (maximum entropy) models. We report on the system's performance with gazetteers of different types and different sizes, using test material from the MUC-7 competition. We show that, for the text type

Early Results for Named Entity Recognition with Conditional Random Fields, Feature Induction and Web-Enhanced Lexicons

by Andrew Mccallum, Wei Li , 2003
"... This paper presents a feature induction method for CRFs. Founded on the principle of constructing only those feature conjunctions that significantly increase loglikelihood, the approach builds on that of Della Pietra et al (1997), but is altered to work with conditional rather than joint probabiliti ..."
Abstract - Cited by 267 (12 self) - Add to MetaCart
probabilities, and with a mean-field approximation and other additional modifications that improve efficiency specifically for a sequence model. In comparison with traditional approaches, automated feature induction offers both improved accuracy and significant reduction in feature count; it enables the use

A golden resource for named entity recognition in Portuguese

by Diana Santos, Nuno Cardoso
"... Abstract. This paper presents a collection of texts manually annotated with named entities in context, which was used for HAREM, the first evaluation contest for named entity recognizers for Portuguese. We discuss the options taken and the originality of our approach compared with previous evaluatio ..."
Abstract - Cited by 2 (2 self) - Add to MetaCart
Abstract. This paper presents a collection of texts manually annotated with named entities in context, which was used for HAREM, the first evaluation contest for named entity recognizers for Portuguese. We discuss the options taken and the originality of our approach compared with previous

Comparative Analysis of Portuguese Named Entities Recognition Tools

by Daniela O F Amaral , Evandro B Fonseca , Lucelene Lopes , Renata Vieira
"... Abstract This paper describes an experiment to compare four tools to recognize named entities in Portuguese texts. The experiment was made over the HAREM corpora, a golden standard for named entities recognition in Portuguese. The tools experimented are based on natural language processing techniqu ..."
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Abstract This paper describes an experiment to compare four tools to recognize named entities in Portuguese texts. The experiment was made over the HAREM corpora, a golden standard for named entities recognition in Portuguese. The tools experimented are based on natural language processing

Learning Named Entity Recognition in Portuguese from Spanish

by Thamar Solorio, Aurelio López López, Luis Enrique Erro
"... Abstract. We present here a practical method for adapting a NER system for Spanish to Portuguese. The method is based on training a machine learning algorithm, namely a C4.5, using internal and external features. The external features are provided by a NER system for Spanish, while the internal feat ..."
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Abstract. We present here a practical method for adapting a NER system for Spanish to Portuguese. The method is based on training a machine learning algorithm, namely a C4.5, using internal and external features. The external features are provided by a NER system for Spanish, while the internal

Named entity recognition in tweets: An experimental study.

by Alan Ritter , Mausam Sam Clark , Oren Etzioni - In Proceedings of Empirical Methods for Natural Language Processing EMNLP, , 2011
"... Abstract People tweet more than 100 Million times daily, yielding a noisy, informal, but sometimes informative corpus of 140-character messages that mirrors the zeitgeist in an unprecedented manner. The performance of standard NLP tools is severely degraded on tweets. This paper addresses this issu ..."
Abstract - Cited by 143 (11 self) - Add to MetaCart
this issue by re-building the NLP pipeline beginning with part-of-speech tagging, through chunking, to named-entity recognition. Our novel T-NER system doubles F 1 score compared with the Stanford NER system. T-NER leverages the redundancy inherent in tweets to achieve this performance, using Labeled

Design challenges and misconceptions in named entity recognition

by Lev Ratinov, Dan Roth - PROCEEDINGS OF THE THIRTEENTH CONFERENCE ON COMPUTATIONAL NATURAL LANGUAGE LEARNING (CONLL) , 2009
"... We analyze some of the fundamental design challenges and misconceptions that underlie the development of an efficient and robust NER system. In particular, we address issues such as the representation of text chunks, the inference approach needed to combine local NER decisions, the sources of prior ..."
Abstract - Cited by 142 (8 self) - Add to MetaCart
knowledge and how to use them within an NER system. In the process of comparing several solutions to these challenges we reach some surprising conclusions, as well as develop an NER system that achieves 90.8 F1 score on the CoNLL-2003 NER shared task, the best reported result for this dataset.

Entity-Based Cross-Document Coreferencing Using the Vector Space Model

by Amit Bagga , 1998
"... Cross-document coreference occurs when the same person, place, event, or concept is discussed in more than one text source. Computer recognition of this phenomenon is important because it helps break "the document boundary " by allowing a user to ex-amine information about a partic ..."
Abstract - Cited by 232 (6 self) - Add to MetaCart
particular entity from multiple text sources at the same time. In this paper we describe a cross-document coreference resolution algorithm which uses the Vector Space Model to re-solve ambiguities between people having the same name. In addition, we also describe a scoring algo-rithm for evaluating the cross

Named Entity Recognition through Classifier Combination

by Radu Florian, Abe Ittycheriah, Hongyan Jing, Tong Zhang - IN PROCEEDINGS OF CONLL-2003 , 2003
"... This paper presents a classifier-combination experimental framework for named entity recognition in which four diverse classifiers (robust linear classifier, maximum entropy, transformation-based learning, and hidden Markov model) are combined under different conditions. When no gazetteer or o ..."
Abstract - Cited by 116 (5 self) - Add to MetaCart
This paper presents a classifier-combination experimental framework for named entity recognition in which four diverse classifiers (robust linear classifier, maximum entropy, transformation-based learning, and hidden Markov model) are combined under different conditions. When no gazetteer

Combining rule-based and statistical methods for named entity recognition in portuguese

by Eduardo Ferreira, João Balsa, António Branco - In V Workshop em Tecnologia da Informação e da Linguagem Humana , 2007
"... Abstract. We present and discuss a tool for the recognition of expressions for named entities in Portuguese that resorts to a rule-based approach when dealing with numbers, measures, time and addresses, and uses a hybrid approach when dealing with names. The expressions for named entities are delimi ..."
Abstract - Cited by 5 (1 self) - Add to MetaCart
Abstract. We present and discuss a tool for the recognition of expressions for named entities in Portuguese that resorts to a rule-based approach when dealing with numbers, measures, time and addresses, and uses a hybrid approach when dealing with names. The expressions for named entities
Results 1 - 10 of 1,093