Báo cáo khoa học: "Unsupervised Learning of Field Segmentation Models for Information Extraction" pot

... Proceedings of the 43rd Annual Meeting of the ACL, pages 371–378, Ann Arbor, June 2005. c 2005 Association for Computational Linguistics Unsupervised Learning of Field Segmentation Models for Information ... consists of de- scriptions of attributes of an item or offer, and a set of ads for similar items share the same attributes. In these cases, the fields presen...

Ngày tải lên: 23/03/2014, 19:20

... Scoring Models The first two examples use the joint probability of the prefix and suffix, with a smoothing back-off (the product of the individual probabilities). Scor- ing models of this form proved ... reliable and are a very important part of the information extracted from the parallel corpus. Therefore, the score of a candidate stem should be based on the score of the corre...

Ngày tải lên: 08/03/2014, 04:22

... France emmanuel.dupoux@gmail.com Abstract Accurate unsupervised learning of phonemes of a language directly from speech is demon- strated via an algorithm for joint unsupervised learning of the topology and parameters of a hidden Markov ... that the original application of SSS was for learning Figure 1: Modified four-way split of a state s. 2. For each HMM state s, comp...

Ngày tải lên: 08/03/2014, 01:20

... (i.e., the CER of the hy- potheses with the minimum number of errors) is presented in Table 1, indicating the upper bound on performance. We also note in Table 1 that the per- formance of the conversion ... 0. For both DLM_1 and DLM_2, models with the parsing weight achieve better performance; we 7 For a detailed description of the baseline trigram model, see Gao et al...

Ngày tải lên: 17/03/2014, 06:20

... linking the ends of a chain of rela- tions. This scheme, informally used previously for combining HYPERNYM with other relations, has not been studied for arbitrary pairs of relations. For example, ... value of the primitive for the inverse relation: id. means it takes the same; op. the opposite. The opposite of − is +, the opposite of + is −, and the opposite of 0 is 0....

Ngày tải lên: 23/03/2014, 16:20

... could potentially provide valuable information. We discuss both of these extensions next. 2.1.1 The Case for Arguments The Chambers and Jurafsky (2008) narrative chains do not specify what type of ... 13 of our 20 narra- tives to FrameNet (for the remaining 7, no frame contained more than one of the six verbs). The remaining 13 schemas contained 6 verbs each for a total of 78...

Ngày tải lên: 23/03/2014, 16:21

... transitive rule: if run BEFORE fall and fall BEFORE injured then run BEFORE injured This increases the number of relations from 37519 to 45619. Perhaps more importantly for our task, of all the added ... in question (whether for inclusion or for decisions of inference). Given a list of observed verb/dependency counts, we approximate the pointwise mutual information (PMI) by: p...

Ngày tải lên: 31/03/2014, 00:20

... of inside and outside scores for all cells in O(n 4 ) time. However, even this can be slow for large values of n. Therefore we describe an Figure 1: (a) shows the original tic-tac-toe score for ... strengths of Bayesian mod- eling and synchronous grammar in unsu- pervised learning of basic translation phrase pairs. The structured space of a synchronous grammar is a natural fi...

Ngày tải lên: 17/03/2014, 02:20

... one of predefined patterns, such as ”When did Jack Welch retire from GE?” to the pattern ”When+did+NP+Verb+NPorPP”. For each ques- tion pattern, there is a set of syntactic structures for potential ... otherwise. α is a factor to discount the co-occurrence value for long paths. It is set to the inverse proportion of the sum of path lengths of the path pair. 892 3.4 Approximate...

Ngày tải lên: 08/03/2014, 02:21

... strongly prefer frequency information, e.g., DF. 4.3 Performances of Different FS Methods It is worth noting that learning parameters in WFO is very important for its good performance. We use 9-fold ... 3.3 Information Gain (IG) IG measures the number of bits of information obtained for category prediction by recognizing the presence or absence of a term in a docum...

Ngày tải lên: 30/03/2014, 23:20