The performance of multilingual pretrained models is highly dependent on the availability of monolingual or parallel text present in a target language. Thus, the majority of the world's languages cannot benefit from recent progress in NLP as they have no or limited textual data. To expand possibilities of using NLP technology in these under-represented languages, we systematically study strategies that relax the reliance on conventional language resources through the use of bilingual lexicons, an alternative resource with much better language coverage. We analyze different strategies to synthesize textual or labeled data using lexicons, and how this data can be combined with monolingual or parallel text when available. For 19 under-represented languages across 3 tasks, our methods lead to consistent improvements of up to 5 and 15 points with and without extra monolingual text respectively. Overall, our study highlights how NLP methods can be adapted to thousands more languages that are under-served by current technology
Speech recognition systems for irregularly-spelled languages like English normally require hand-written pronunciations. In this paper, we describe a system for automatically obtaining pronunciations of words for which pronunciations are not available, but for which transcribed data exists. Our method integrates information from the letter sequence and from the acoustic evidence. The novel aspect of the problem that we address is the problem of how to prune entries from such a lexicon (since, empirically, lexicons with too many entries do not tend to be good for ASR performance). Experiments on…
Text classification has seen an increased use in both academic and industry settings. Though rule based methods have been fairly successful, supervised machine learning has been shown to be most successful for most languages, where most research was done on English. In this article, the success of lexicon analysis, support vector machines, and extreme gradient boosting for the task of text classification and sentiment analysis are evaluated in Turkish and a pretrained transformer based classifier is proposed, outperforming previous methods for Turkish text classification. In the context of tex…
Tangut Word Segmentation under Extreme Resource Scarcity: Integrating Traditional Lexicons and Unlabeled Text
Chinese Academy of Social Sciences（中国社会科学院）；University of Chinese Academy of Social Sciences（中国社会科学院大学）；Rixin College, Tsinghua University（清华大学日新书院）；Institute of Linguistics, Chinese Academy of Social Sciences（中国社会科学院语言研究所）；Institute of Ethnology and Anthropology, Chinese Academy of Social Sciences（中国社会科学院民族学与人类学研究所）；School of Software and Microelectronics, Peking University（北京大学软件与微电子学院）
University of California, San Diego（加州大学圣地亚哥分校）；Microsoft Research Asia（微软亚洲研究院）；Sun Yat-sen University（中山大学）
In this paper, we propose LaPraDoR, a pretrained dual-tower dense retriever that does not require any supervised data for training. Specifically, we first present Iterative Contrastive Learning (ICoL) that iteratively trains the query and document encoders with a cache mechanism. ICoL not only enlarges the number of negative instances but also keeps representations of cached examples in the same hidden space. We then propose Lexicon-Enhanced Dense Retrieval (LEDR) as a simple yet effective way to enhance dense retrieval with lexical matching. We evaluate LaPraDoR on the recently proposed BEIR …
Successful methods for unsupervised neural machine translation (UNMT) employ crosslingual pretraining via self-supervision, often in the form of a masked language modeling or a sequence generation task, which requires the model to align the lexical- and high-level representations of the two languages. While cross-lingual pretraining works for similar languages with abundant corpora, it performs poorly in low-resource and distant languages. Previous research has shown that this is because the representations are not sufficiently aligned. In this paper, we enhance the bilingual masked language m…
ProMap: Effective Bilingual Lexicon Induction via Language Model Prompting
College of Computing, Mohammed VI Polytechnic University（穆罕默德六世理工大学计算学院）；Deep Learning & Natural Language Processing Group, The University of British Columbia（不列颠哥伦比亚大学深度学习与自然语言处理组）；Department of Natural Language Processing & Department of Machine Learning, MBZUAI（穆罕默德·本·扎耶德人工智能大学自然语言处理系与机器学习系）；Department of Electrical & Computer Engineering, University of Sherbrooke（舍布鲁克大学电气与计算机工程系）
We translate a closed text that is known in advance into a severely low resource language by leveraging massive source parallelism. In other words, given a text in 124 source languages, we translate it into a severely low resource language using only ~1,000 lines of low resource data without any external help. Firstly, we propose a systematic method to rank and choose source languages that are close to the low resource language. We call the linguistic definition of language family Family of Origin (FAMO), and we call the empirical definition of higher-ranked languages using our metrics Family …
University of Trento（特伦托大学）；National University of Mongolia（蒙古国立大学）
The Universal Knowledge Core (UKC) is a large multilingual lexical database with a focus on language diversity and covering over a thousand languages. The aim of the database, as well as its tools and data catalogue, is to make the somewhat abstract notion of diversity visually understandable for humans and formally exploitable by machines. The UKC website lets users explore millions of individual words and their meanings, but also phenomena of cross-lingual convergence and divergence, such as shared interlingual meanings, lexicon similarities, cognate clusters, or lexical gaps. The UKC LiveLa…
University of Washington（华盛顿大学）；Microsoft Research（微软研究院）
Many real-world applications require automated data annotation, such as identifying tissue origins based on gene expressions and classifying images into semantic categories. Annotation classes are often numerous and subject to changes over time, and annotating examples has become the major bottleneck for supervised learning methods. In science and other high-value domains, large repositories of data samples are often available, together with two sources of organic supervision: a lexicon for the annotation classes, and text descriptions that accompany some data samples. Distant supervision has …
Stanford University（斯坦福大学）；University of Groningen（格罗宁根大学）；University of Hawai’i at Mānoa（夏威夷大学马诺阿分校）；University of Washington（华盛顿大学）；University of Queensland（昆士兰大学）
Recent research using pre-trained transformer models suggests that just 10 minutes of transcribed speech may be enough to fine-tune such a model for automatic speech recognition (ASR) -- at least if we can also leverage vast amounts of text data (803 million tokens). But is that much text data necessary? We study the use of different amounts of text data, both for creating a lexicon that constrains ASR decoding to possible words (e.g. *dogz vs. dogs), and for training larger language models that bias the system toward probable word sequences (e.g. too dogs vs. two dogs). We perform experiments…
Recent research shows synthetic data as a source of supervision helps pretrained language models (PLM) transfer learning to new target tasks/domains. However, this idea is less explored for spatial language. We provide two new data resources on multiple spatial language processing tasks. The first dataset is synthesized for transfer learning on spatial question answering (SQA) and spatial role labeling (SpRL). Compared to previous SQA datasets, we include a larger variety of spatial relation types and spatial expressions. Our data generation process is easily extendable with new spatial expres…
The IMPACT-es diachronic corpus of historical Spanish compiles over one hundred books --containing approximately 8 million words-- in addition to a complementary lexicon which links more than 10 thousand lemmas with attestations of the different variants found in the documents. This textual corpus and the accompanying lexicon have been released under an open license (Creative Commons by-nc-sa) in order to permit their intensive exploitation in linguistic research. Approximately 7% of the words in the corpus (a selection aimed at enhancing the coverage of the most frequent word forms) have been…
Text data are being used as a lens through which human cognition can be studied at a large scale. Methods like emotion analysis are now in the standard toolkit of computational social scientists but typically rely on third-person annotation with unknown validity. As an alternative, this paper introduces online emotion induction techniques from experimental behavioural research as a method for text-based emotion analysis. Text data were collected from participants who were randomly allocated to a happy, neutral or sad condition. The findings support the mood induction procedure. We then examine…
Yale University（耶鲁大学）；Facebook AI（脸书人工智能研究院）；Nanyang Technological University（南洋理工大学）；Renmin University of China（中国人民大学）
Models pretrained with self-supervised objectives on large text corpora achieve state-of-the-art performance on English text summarization tasks. However, these models are typically fine-tuned on hundreds of thousands of data points, an infeasible requirement when applying summarization to new, niche domains. In this work, we introduce a novel and generalizable method, called WikiTransfer, for fine-tuning pretrained models for summarization in an unsupervised, dataset-specific manner. WikiTransfer fine-tunes pretrained models on pseudo-summaries, produced from generic Wikipedia data, which con…
Language Technology Lab, University of Cambridge（剑桥大学语言技术实验室）；Faculty of Industrial Engineering and Management, Technion, IIT（以色列理工学院工业工程与管理学院）
Performance in cross-lingual NLP tasks is impacted by the (dis)similarity of languages at hand: e.g., previous work has suggested there is a connection between the expected success of bilingual lexicon induction (BLI) and the assumption of (approximate) isomorphism between monolingual embedding spaces. In this work we present a large-scale study focused on the correlations between monolingual embedding space similarity and task performance, covering thousands of language pairs and four different tasks: BLI, parsing, POS tagging and MT. We hypothesize that statistics of the spectrum of each mon…
University of Cambridge（剑桥大学）；University of Southern California（南加州大学）
Knowledge bases (KBs) contain plenty of structured world and commonsense knowledge. As such, they often complement distributional text-based information and facilitate various downstream tasks. Since their manual construction is resource- and time-intensive, recent efforts have tried leveraging large pretrained language models (PLMs) to generate additional monolingual knowledge facts for KBs. However, such methods have not been attempted for building and enriching multilingual KBs. Besides wider application, such multilingual KBs can provide richer combined knowledge than monolingual (e.g., En…
Segment, Embed, and Align: A Universal Recipe for Aligning Subtitles to Signing
VGG, Dept. of Engineering Science, University of Oxford（视觉感知与计算实验室，工程科学系，牛津大学）；University of Zurich（苏黎世大学）；KAIST（韩国科学技术院）；LIGM, CNRS, Univ Gustave Eiffel, ENPC, IP Paris（LIGM，国家科学研究中心，古斯塔夫·埃菲尔大学，巴黎理工大学，IP巴黎）
University at Buffalo（布法罗大学）；JD Finance America Corporation（京东金融美国公司）
Large-scale pretrained language models have shown thrilling generation capabilities, especially when they generate consistent long text in thousands of words with ease. However, users of these models can only control the prefix of sentences or certain global aspects of generated text. It is challenging to simultaneously achieve fine-grained controllability and preserve the state-of-the-art unconditional text generation capability. In this paper, we first propose a new task named "Outline to Story" (O2S) as a test bed for fine-grained controllable generation of long text, which generates a mult…
Transformers Boost the Performance of Decision Trees on Tabular Data across Sample Sizes
University of Maryland（马里兰大学）；University of Toronto（多伦多大学）；Meta；Amazon（亚马逊公司）；New York University（纽约大学）；University of Freiburg（弗莱堡大学）；Columbia University（哥伦比亚大学）
