1,721,112 research outputs found
Lattice score based data cleaning for phrase-based statistical machine translation
Statistical machine translation relies heavily
on parallel corpora to train its models
for translation tasks. While more and
more bilingual corpora are readily available,
the quality of the sentence pairs
should be taken into consideration. This
paper presents a novel lattice score-based
data cleaning method to select proper sentence
pairs from the ones extracted from a
bilingual corpus by the sentence alignment
methods. The proposed method is carried
out as follows: firstly, an initial phrasebased
model is trained on the full sentencealigned
corpus; then for each of the sentence
pairs in the corpus, word alignments
are used to create anchor pairs and sourceside
lattices; thirdly, based on the translation
model, target-side phrase networks
are expanded on the lattices and Viterbi
searching is used to find approximated decoding
results; finally, BLEU score thresholds
are used to filter out the low-score
sentence pairs for the data cleaning purpose.
Our experiments on the FBIS corpus
showed improvements of BLEU score
from 23.78 to 24.02 in Chinese-English
Chris Callison-Burch
We present two methods for the automatic creation of parallel corpora. Whereas previous work into the automatic construction of parallel corpora has focused on harvesting them from the web, we examine the use of existing parallel corpora to bootstrap data for new language pairs. First, we extend existing parallel corpora using co-training, wherein machine translations are selectively added to training corpora with multiple source texts. Retraining translation models yields modest improvements. Second, we simulate the creation of training data for a language pair for which a parallel corpus is not available. Starting with no human translations from German to English we produce a German to English translation model with 45% accuracy using parallel corpora in other languages. This suggests the method may be useful in the creation of parallel corpora for languages with scarce resources.
Crowdsourcing for Grammatical Error Correction
Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the owner/author(s). Copyright is held by the author/owner(s)
Co-training for Statistical Machine Translation
We present a novel co-training method for statistical machine translation. Since cotraining requires independent views on the data, with each view being sufficient for the labeling task, we use source strings in multiple languages as views on translation. Co-training for statistical machine translation is therefore a type of multisource translation. We show that using five language pairs our approach can yield improvements of up to 2.5 % in word error rates for translation models. Our experiments suggest that co-training is even more effective for languages with highly impoverished parallel corpora: starting with no human translations from German to English we produce a German to English translation model with 45 % accuracy using parallel corpora in other languages
Data cleaning for word alignment
Parallel corpora are made by human beings. However, as an MT system is an aggregation of state-of-the-art NLP technologies without any intervention of human beings, it is unavoidable that quite a few sentence pairs are beyond its analysis and that will therefore not contribute
to the system. Furthermore, they in turn may act against our objectives to make the overall performance worse. Possible unfavorable items are n : m mapping objects,
such as paraphrases, non-literal translations, and multiword expressions. This paper presents a pre-processing method which detects such unfavorable items before
supplying them to the word aligner under the assumption that their frequency is low, such as below 5 percent. We show an improvement of Bleu score from 28.0 to 31.4 in English-Spanish and from 16.9 to 22.1 in German-English
- …
