Memory-based context-sensitive spelling correction at web scale

Traitement Automatique des Langues (TAL), 53:3, 61-99., 2012

Flor M. (2012). Four types of context for automatic spelling correction. Traitement Automatique des Langues (TAL), 53:3, 61-99. This paper presents an investigation on using four types of contextual information for improving the accuracy of automatic correction of single-token non-word misspellings. The task is framed as contextually-informed re-ranking of correction candidates. Immediate local context is captured by word n-grams statistics from a Web-scale language model. The second approach measures how well a candidate correction fits in the semantic fabric of the local lexical neighborhood, using a very large Distributional Semantic Model. In the third approach, recognizing a misspelling as an instance of a recurring word can be useful for reranking. The fourth approach looks at context beyond the text itself. If the approximate topic can be known in advance, spelling correction can be biased towards the topic. Effectiveness of proposed methods is demonstrated with an annotated corpus of 3,000 student essays from international high-stakes English language assessments. The paper also describes an implemented system that achieves high accuracy on this task."

2010

This paper makes three significant extensions to a noisy channel speller designed for standard written text to target the challenging domain of search queries. First, the noisy channel model is subsumed by a more general ranker, which allows a variety of features to be easily incorporated. Second, a distributed infrastructure is proposed for training and applying Web scale n-gram language models. Third, a new phrase-based error model is presented. This model places a probability distribution over transformations between multi-word phrases, and is estimated using large amounts of query-correction pairs derived from search logs. Experiments show that each of these extensions leads to significant improvements over the stateof-the-art baseline methods.

Proceedings of the …, 2011

We propose a novel way of incorporating dependency parse and word co-occurrence information into a state-of-the-art web-scale n-gram model for spelling correction. The syntactic and distributional information provides extra evidence in addition to that provided by a web-scale n-gram corpus and especially helps with data sparsity problems. Experimental results show that introducing syntactic features into n-gram based models significantly reduces errors by up to 12.4% over the current state-of-the-art. The ...

Proceedings of the 2009 Conference on …, 2009

We present a method for detecting and correcting multiple real-word spelling errors using the Google Web 1T 3-gram data set and a normalized and modified version of the Longest Common Subsequence (LCS) string matching algorithm. Our method is focused mainly on how to improve the detection recall (the fraction of errors correctly detected) and the correction recall (the fraction of errors correctly amended), while keeping the respective precisions (the fraction of detections or amendments that are correct) as high as possible. Evaluation results on a standard data set show that our method outperforms two other methods on the same task.

Proceedings of the Fourteenth Workshop on Innovative Use of NLP for Building Educational Applications, 2019

Spelling correction has attracted a lot of attention in the NLP community. However, models have been usually evaluated on artificially-created or proprietary corpora. A publicly-available corpus of authentic misspellings, annotated in context, is still lacking. To address this, we present and release an annotated data set of 6,121 spelling errors in context, based on a corpus of essays written by English language learners. We also develop a minimally-supervised context-aware approach to spelling correction. It achieves strong results on our data: 88.12% accuracy. This approach can also train with a minimal amount of annotated data (performance reduced by less than 1%). Furthermore, this approach allows easy porta-bility to new domains. We evaluate our model on data from a medical domain and demonstrate that it rivals the performance of a model trained and tuned on in-domain data.

2010

This paper explores the use of clickthrough data for query spelling correction. First, large amounts of query-correction pairs are derived by analyzing users' query reformulation behavior encoded in the clickthrough data. Then, a phrase-based error model that accounts for the transformation probability between multi-term phrases is trained and integrated into a query speller system. Experiments are carried out on a human-labeled data set. Results show that the system using the phrase-based error model outperforms significantly its baseline systems. 3 Clickthrough Data and Spelling Correction This section describes the way the query-correction pairs are extracted from click

Empirical Methods in Natural Language Processing, 2009

We present a method for detecting and correcting multiple real-word spelling er- rors using the Google Web 1T 3-gram data set and a normalized and modified ver- sion of the Longest Common Subsequence (LCS) string matching algorithm. Our method is focused mainly on how to im- prove the detection recall (the fraction of errors correctly detected) and the correc- tion

2001

Abstract The main challenge in an effort to build a realistic system with context-sensitive inference capabilities, beyond accuracy, is scalability. This paper studies this problem in the context of a learning-based approach to context sensitive text correction–the task of fixing spelling errors that result in valid words, such as substituting to for too, casual for causal, and so on. Research papers on this problem have developed algorithms that can achieve fairly high accuracy, in many cases over 90%.

2005

ABSTRACT This paper discusses the issues involved in an information retrieval system when spelling errors are encountered in a query. We look at two classical algorithms that may be used to correct these errors and their consequent effect on the system's performance. The algorithms are the Levenshtein Distance and the Longest Common Subsequence. We experiment on a variety of test data and explore the impact of certain errors on an information retrieval system.

Proceedings 24th Australian Computer Science Conference. ACSC 2001

This paper describes a new approach to automatically learn contextual knowledge for spelling and grammar correctionwe aim particularly to deal with cases where the words are all in the dictionary and so it is not obvious that there is an error. Traditional approaches are dictionary based, or use elementary tagging or partial parsing of the sentence to obtain context knowledge. Our approach uses aflx information and only the most frequent words to reduce the complexity in terms of training time and running time for context-sensitive spelling correction. We build large scale confused word sets based on keyboard adjacency and apply our new approach to learn the contextual knowledge to detect and correct them. We explore the perjlormance of autocorrection under conditions where significance and probabilty are set by the user.