Báo cáo khoa học: "Improving IBM Word-Alignment Model " pdf

... iteration of EM in using Model 1 to initialize their Model 2, and Och and Ney (2003) stop af- ter five iterations in using Model 1 to initialize the HMM word-alignment model. Both of these are ... estimation method to initialize, or replace, EM training of model parameters. 1 Introduction IBM Model 1 (Brown et al., 1993a) is a word- alignment model that is widely used in worki...

Ngày tải lên: 23/03/2014, 19:20

... For our training, we ran GIZA++ for five iterations each of Model 1, the HMM, Model 3, and Model 4. Variational Bayes was only used for Model 1. Figure 1 shows how VB, and different values of α ... the four models in- dividually, and when it is used for all four models simultaneously. We saw the most overall improve- ment when VB was used only for Model 1; using VB for all four model...

Ngày tải lên: 23/03/2014, 14:20

... 2008. c 2008 Association for Computational Linguistics Improving the Performance of the Random Walk Model for Answering Complex Questions Yllias Chali and Shafiq R. Joty University of Lethbridge 4401 ... and shallow semantic information in measuring similarity between the sentences in the random walk model for answering complex ques- tions. We argue that for this task, similarity mea- sur...

Ngày tải lên: 23/03/2014, 17:20

... method of combining two criteria in model pruning. Experimental results show that the combined criterion consistently leads to smaller models than the models pruned using either of the criteria ... method of combining two pruning criteria in model pruning. Our results show that the combined criterion consistently leads to smaller models than the models pruned using either of the...

Ngày tải lên: 23/03/2014, 20:20

... given an unordered list of words, typically using an n-gram language model to select the best word ordering. N-gram language models appear to do well at a local level when examining word sequences ... probability. We refer to this tree linearisation method as the Lan- guage Model Ordering (LMO). 4 Using an Argument Satisfaction Model 4.1 Assigning Words to Argument Positions One limitat...

Ngày tải lên: 24/03/2014, 03:20

... limitation of this evaluation is that the human judgments are on pairs 873

Ngày tải lên: 19/02/2014, 19:20

... problem based on a two-step hybrid model: a generative model for hierarchical topic discovery and a regression model for inference. We investigate if a hierarchi- cal model can be adopted to discover ... hierarchical model and re- gression model to score sentences in new docu- ments, eliminating the need for building a genera- tive model for new document clusters. 3 Summary-Focus...

Ngày tải lên: 20/02/2014, 04:20

... series of five models (IBM Models). IBM Model 1 only em- ploys the word translation model to calculate the probabilities of alignments. In IBM Model 2, both the word translation model and position ... dis- tribution model are used. IBM Model 3, 4 and 5 consider the fertility model in addition to the word translation model and position distribution model. And these...

Ngày tải lên: 20/02/2014, 04:20

... the degree of each word pair through a graph-based model in the following section. 3.2 HITS Model We propose an opinion retrieval model based on HITS, a popular graph ranking algorithm ... re- trieval model, and further assumed that all re- trieved documents contained relevant opinions. (2) Doc: The 2-stage document-based opinion retrieval model was adopted. The model use...

Ngày tải lên: 20/02/2014, 04:20

Ngày tải lên: 20/02/2014, 04:20