generation as dependency parsing

Ngày tải lên: 08/03/2014, 07:20

... (a) the last token in each path with the sequence of dependency labels along the corresponding path; and (b) the word to be classified, the last token in each path, and the sequence of dependency ... attempts to optimize the Labeled Attachment Score (LAS) between the dependency trees and con- verted gold dependency trees. LAS is approximate for two reasons. First, it is much more local than the ... BioNLP’09 shared task and show that our approach obtains competitive results. 2 Related Work The pioneering work of Miller et al. (1997) was the first, to our knowledge, to propose parsing as a framework...

Ngày tải lên: 20/02/2014, 04:20

Ngày tải lên: 08/03/2014, 01:20

Ngày tải lên: 23/03/2014, 18:20

... constituents such as chunks have not been used in sample selection for parsing. We use Japanese dependency parsing as a target task in this study since a simple and efficient algorithm of parsing is ... effective. 3 Japanese Parsing 3.1 Syntactic Units A basic syntactic unit used in Japanese parsing is a bunsetsu, the concept of which was initially in- troduced by Hashimoto (1934). We assume that in ... Learning for Japanese Dependency Parsing Manabu Sassano Yahoo Japan Corporation Midtown Tower, 9-7-1 Akasaka, Minato-ku, Tokyo 107-6211, Japan msassano@yahoo-corp.jp Sadao Kurohashi Graduate School...

Ngày tải lên: 20/02/2014, 04:20

... Laboratory Massachusetts Institute of Technology roiri@csail.mit.edu Abstract Dependency parsing is a central NLP task. In this paper we show that the common eval- uation for unsupervised dependency parsing is ... for reviews). For unsupervised dependency parsing, the Dependency Model with Valence (DMV) (Klein and Manning, 2004) was the first to beat the simple right-branching baseline. A technical description ... proper evaluation of unsupervised parsing algo- rithms against a gold standard. The first way was to modify the parameters of the parsing algorithms so that in cases where such prob- lematic decisions...

Ngày tải lên: 20/02/2014, 04:20

... be applied to dependency parsing. We focus on Shift-Reduce transition-based parsing proposed by Nivre et al. (2004). In this class of algorithms, at any given step, the parser has to choose among ... state-of-the-art dependency pars- ing systems. Surdeanu and Manning (2010) com- pare different parsing models using CoNLL 2008 shared task dataset (Surdeanu et al., 2008), which is the same as our dataset. ... Integrating graph- based and transition-based dependency parsers. Pro- ceedings of ACL-08: HLT, pages 950–958. J. Nivre, J. Hall, and J. Nilsson. 2004. Memory-based dependency parsing. In Proceedings...

Ngày tải lên: 20/02/2014, 04:20

... Y(x) makes dependency pars- ing a structured classification problem. 2.2 Arc Factorization and Locality There has been much recent work on dependency parsing using graph-based, transition-based, and hybrid ... exploitation of global features and constraints in parsing applica- tions, leading to more powerful models. Riedel and Clarke (2006) cast dependency parsing as an ILP, but efficient formulations remain ... rela- tionships between words. Lately, this formalism has been used as an alternative to phrase-based parsing for a variety of tasks, ranging from ma- chine translation (Ding and Palmer, 2005) to...

Ngày tải lên: 20/02/2014, 07:20

... nodes from Σ). Hence, the complexity of deterministic parsing is O(n) in the worst case (as well as in the best case). 3.2 Unrestricted Dependency Parsing We now consider what happens when we add ... (2006), which was the best performing transition-based system in the CoNLL-X shared task. 2 Table 1 shows the labeled parsing accuracy of the parsers measured in two ways: attachment score (AS) is the ... still has not found a satisfactory solution in data-driven dependency parsing is the treatment of discontinuous syntactic constructions, usually modeled by non-projective dependency trees, as illustrated...

Ngày tải lên: 20/02/2014, 07:20

... the case of dependency parsing for Czech, (McDonald et al., 2005b) even outperforms projective parsing, and was one of the top systems in the CoNLL-06 shared task in multilingual dependency parsing. 2.1 ... statis- tically very significant (p ≤ .01). 2 Dependency parsing for machine translation In this section, we review dependency parsing for- mulated as a maximum spanning tree problem (McDonald ... to reduce the worst-case complexity of bilexical parsing, which otherwise requires O(n 4 ) for bilexical constituency-based parsing. While it seems difficult to improve the asymptotic running time...

Ngày tải lên: 20/02/2014, 07:20

... prop- erty syn) as the co-occurrence of rs and syn, v. The dimension of the hidden class was 100. The total number of rs, syn, v pairs was 1,016,508, v was 18,423, and rs was 1,490. The particle ... work on Japanese dependency analysis has as- sumed that all the dependency relations are inde- pendent of one another. It is therefore necessary to also consider such a constraint as a feature for contextual ... T We defined case element as a pair of a noun and following particles. For the dependency structure we assume the conditional probability P (es i (T )|v i (T )) that the set of case elements es i (T...

Ngày tải lên: 20/02/2014, 12:20

... learned classifiers in a pipeline fashion, where a task is de- composed into several stages and stage classifiers are used sequentially, where each stage may use the outcome of previous stages as its ... to generalize this work to non-projective dependency parsing, as well as attempting to incorporate additional sources of information (e.g., shallow parsing in- formation) into the pipeline process. 6 ... another strong reason to use Step Back, since the classification becomes more accurate – a more natural class of actions, with a smaller number of candidate actions. Once the parsing algorithm,...

Ngày tải lên: 20/02/2014, 12:20

... We deliberately avoid reasoning about utterances as co- ordinated rational behavior, as earlier systems did; this allows us to get by with a much simpler logic. The problem we solve encompasses the genera- tion ... this state; all other atoms are as- sumed to be false. Actions have a number of param- eters, as well as a precondition and effect, both of which are logical formulas. When a planner tries to apply ... proving to prob- lem solving. In Workshop Planning as Combinatorial Search, AIPS-98. A. Koller and K. Striegnitz. 2002. Generation as depen- dency parsing. In Proc. 40th ACL, Philadelphia. D. V....

Ngày tải lên: 20/02/2014, 12:20

... number of classification tasks related to incremental dependency parsing. These tasks were con- ventional multiclass classification, hiearchi- cal classification, and a structured classifica- tion task: ... logistic online learning performs as well as margin-based methods. Logistic models are easily extended to us- ing kernels; that this is theoretically well-justified was shown by Zhu and Hastie (2005), who also made ... Multiclass classification results. 3.2 Hierarchical Classification In the second experiment, we used the same train- ing and test set, but considered the selection of the parsing action as a hierarchical...

Ngày tải lên: 20/02/2014, 12:20

... Transformations We assume that the goal in dependency parsing is to construct a labeled dependency graph of the kind de- picted in Figure 1. Formally, we define dependency graphs as follows: 1. Let ... view, projective parsing of non-projective structures has the drawback that it rules out perfect accuracy even as an asymptotic goal. 99 Lifted arc label Path labels Number of labels Baseline d p ... the finite-state dependency parser for Turkish by Oflazer (2003). This is in contrast to dependency treebanks, e.g. Prague Dependency Treebank (Haji ˇ c et al., 2001b), Danish Dependency Treebank...

Ngày tải lên: 20/02/2014, 15:20

... contrast, the PROJECTIVITY constraint is much more controversial. Broadly speaking, we can say that whereas most practical systems for dependency parsing do assume projectivity, most dependency- based ... class of algorithms that derive non- projective dependency graphs by treating every possible word pair as a potential dependency arc. The paper is structured as follows. In section 2 we define dependency ... Nilsson. 2005. Pseudo- projective dependency parsing. Proceedings ACL, pp. 99–106. Joakim Nivre, Johan Hall, and Jens Nilsson. 2004. Memory-based dependency parsing. Proceedings of CoNLL, pp....

Ngày tải lên: 22/02/2014, 02:20

... first-order model, the dependency to h 3 is created after the algorithm has forgotten that h 2 was the last dependent. of what it was in y. The test tree(y) is true iff the dependency graph y satisfies ... Eisner algorithm to second-order dependency parsing. This figure shows how h 1 creates a dependency to h 3 with the second-order knowledge that the last dependent of h 1 was h 2 . This is done through ... intro- duce non-projective edges. However, this system relies on a much slower phrase-structure parser as its base model as well as an auxiliary rerank- ing module. Indeed, our second-order projective parser...

Ngày tải lên: 22/02/2014, 02:20

... can help, as well as investi- gation of more sophisticated models such as SVM or memory-based techniques for correctly identi- fying dependencies. 8 Acknowledgement This research was supported ... linked by the parser to the last IG of the last word as a de- pendent. Table 1 shows the results from our experiments with these baseline parsers and parsers that are based on the three models above. ... tag consisting of only the case marker, as that essentially determines the syntactic function of that IG as a dependent, and only nominals have cases. • If the IG is used as a head, then we use only...

Ngày tải lên: 22/02/2014, 02:20

Ngày tải lên: 07/03/2014, 18:20

Ngày tải lên: 07/03/2014, 22:20