Báo cáo khoa học: "Lexically-Triggered Hidden Markov Models for Clinical Document Coding" pot

... 2011. c 2011 Association for Computational Linguistics Lexically-Triggered Hidden Markov Models for Clinical Document Coding Svetlana Kiritchenko Colin Cherry Institute for Information Technology National ... and rev- enue. Perspectives in Health Information Manage- ment, CAC Proceedings, Fall. M. Collins. 2002. Discriminative training methods for Hidden Markov Models:...

Ngày tải lên: 07/03/2014, 22:20

... (c) is it normal or is it ab- normal? Therefore, when a radiologist looks for information, his search queries most likely con- tain terms from various information sources that provide this kind ... even discus- sions from clinical web discussion boards. From the NCI Thesaurus we can obtain the in- formation that ‘liver lymphoma’ is the synonym for ‘hepatic lymphoma’, for which hold...

Ngày tải lên: 08/03/2014, 21:20

... hit. Enforcing such agreement constraints between hidden variables provides a principled way to cap- ture not only phrasal information but also lexical in- formation. Lexical pieces of information ... second-order grammars with hidden variables. 3 Hidden Variable Models Because they do not stipulate the existence of phrasal nodes, commonly used unlabelled depen- dency models are not...

Ngày tải lên: 17/03/2014, 02:20

... with the self-organizing Markov models to find an optimal sequence of tags for a given word sequence. 5.2 Learning Self-Organizing Markov Models Self-organizing Markov models can be induced from ... result- ing models outperform uniform memory Markov models in a part-of-speech tag- ging task. 1 Introduction Many major NLP tasks can be regarded as prob- lems of finding an opt...

Ngày tải lên: 31/03/2014, 03:20

... constructs new hypotheses by extend- ing existing hypotheses. New hypotheses are placed in appropriate hypothesis stacks. In the simplest case, a new hypothesis extends an existing hypothe- sis by ... element. When a new hypothesis extends an existing hy- pothesis by more than one word, this process is first carried out for the first new word in the hypothe- sis. It is then repeated for the...

Ngày tải lên: 20/02/2014, 04:20

... the following procedure is performed: First, generate a hypotheses list using the N -best hypotheses of a regular search. Second, add to this list, new hy- potheses formed by a single translation-word ... 20.9 German/English 62.0 21.9 61.6 16.5 Table 4: CAT results for the “XRCE” task for 1- best hypothesis and 5-best hypothesis. alternatives before choosing. It is still to be shown if th...

Ngày tải lên: 20/02/2014, 12:20

... language. Those lexicon models lack from context infor- mation that can be extracted from the same paral- lel corpus. This additional information could be: Simple context information: information of the ... surrounding the word pair; Syntactic information: part-of-speech in- formation, syntactic constituent, sentence mood; Semantic information: disambiguation in- formation (e.g. from WordNe...

Ngày tải lên: 20/02/2014, 18:20

... n- gram models and decision-tree models is to make clear that the power of decision-tree models is not in their expressiveness, but instead in how they can be automatically acquired for very ... the model. No information about the legal tags for a word are extracted from the test corpus. In fact, no information other than the words is used from the test corpus. For the sak...

Ngày tải lên: 20/02/2014, 22:20

... backoff models for combining in-domain and 42 out-of-domain data for the purpose of bootstrap- ping a part-of-speech tagger for Chinese, outper- forming standard methods such as EM. 4 Backoff Models ... applied before training and after gener- ating the output in the target language. Normaliza- tion of English/German inflectional morphology to base forms for the purpose of word ali...

Ngày tải lên: 22/02/2014, 02:20

... smoothing for the BiTAM models. We train, for comparison, IBM-1&4 and HMM models with 8 iterations of IBM-1, 7 for HMM and 3 for IBM-4 (1 8 h 7 4 3 ) with Null word and a maximum fertility of 3 for ... (BiTAM) formalism for word alignment in statistical machine transla- tion. Under this formalism, the paral- lel sentence-pairs within a document- pair are assumed to consti...

Ngày tải lên: 17/03/2014, 04:20