DIACRITIC-AWARE YORÙBÁ SPELL CHECKER

Spell checking and correction is still in infancy for Yorùbá language, and existing tools cannot be applied directly to address the problem because Yorùbá language requires extensive use of diacritics for marking phonemes and tone. We addressed this problem by collecting data from on-line sources and from optical character recognition of hard copy of books. The features relevant to spell checking and correction in this language that marks tones (and underdot) were identified through the review of existing spell checking solutions, analysis of the data collected and consultation with relevant Yorùbá Linguistics textbooks. A conceptual model was formulated as a parallel combination of a unigram language model and a language diacritic model to form a dictionary sub-model that is used by Error Detection and Candidate Generation modules. The candidate generation module was implemented as an inverse Levensthein edit-distance algorithm. The system was evaluated using Detection Accuracy (calculated from Precision and Recall) and Suggestion Accuracy (SA) as metrics.Our experimental setups compared the performance of the component subsystems when used alone with the their combination into a unified model. The detection accuracies for each of the models were 93.23%, 94.10% and 95.01% respectively while their suggestion accuracies were 26.94%, 72.10% and 65.89% respectively. In relation to the size of training corpus, the unified model was able to achieve a increase of 1.83% in detection accuracy and 5.27% in suggestion accuracy for 70% increase in size of corpus. The results indicated that each of the sub-models in the dictionary played different roles while the increase in training data does not give a linear proportional increase in performance of the spell checker. The study also showed that spell checking a Yorùbá text was better when attention is paid to the diacritical aspect of the languag

Errors lingüístics en el domini biomèdic: Cap a una tipologia d’errors per a l’espanyol

L’objectiu d’aquest treball és l’anàlisi d’errors continguts en un corpus d’informes mèdics en llenguatge natural i el disseny d’una tipologia d’errors, ja que no hi va haver una revisió sistemàtica sobre verificació i correcció d’errors en documentació clínica en castellà. En el desenvolupament de sistemes automàtics de detecció i correcció, és d’interès aprofundir en la naturalesa dels errors lingüístics que es produeixen en els informes clínics per tal de detectar-los i tractar-los adequadament. Els resultats mostren que els errors d’omissió són els més freqüents en la mostra analitzada i que la longitud de la paraula sens dubte influeix en la freqüència d’error. La tipificació dels patrons d’error proporcionats permet el desenvolupament d’un mòdul basat en coneixements lingüístics, actualment en curs, que serà capaç de millorar el rendiment dels sistemes de correcció de detecció i correcció d’errors per al domini biomèdicThe objective of this work is the analysis of errors contained in a corpus of medical reports in natural language and the design of a typology of errors, as there was no systematic review on verification and correction of errors in clinical documentation in Spanish. In the development of automatic detection and correction systems, it is of great interest to delve into the nature of the linguistic errors that occur in clinical reports, in order to detect and treat them properly. The results show that omission errors are the most frequent ones in the analyzed sample, and that word length certainly influences error frequency. The typification of error patterns provided is enabling the development of a module based on linguistic knowledge, which is currently in progress. This will help to improve the performance of error detection and correction systems for the biomedical domain.This work was supported by the Spanish National Research Agency (AEI) through project LaTe4PSP (PID2019-107652RB-I00/AEI/10.13039/501100011033). Furthermore, the main autor is supported by Ministerio de Universidades of Spain through the national program Ayudas para la formación de profesorado universitario (FPU), with reference FPU16/0332

A Methodology for Generative Spelling Correction via Natural Spelling Errors Emulation across Multiple Domains and Languages

Modern large language models demonstrate impressive capabilities in text generation and generalization. However, they often struggle with solving text editing tasks, particularly when it comes to correcting spelling errors and mistypings. In this paper, we present a methodology for generative spelling correction (SC), which was tested on English and Russian languages and potentially can be extended to any language with minor changes. Our research mainly focuses on exploring natural spelling errors and mistypings in texts and studying the ways those errors can be emulated in correct sentences to effectively enrich generative models' pre-train procedure. We investigate the impact of such emulations and the models' abilities across different text domains. In this work, we investigate two spelling corruption techniques: 1) first one mimics human behavior when making a mistake through leveraging statistics of errors from particular dataset and 2) second adds the most common spelling errors, keyboard miss clicks, and some heuristics within the texts. We conducted experiments employing various corruption strategies, models' architectures and sizes on the pre-training and fine-tuning stages and evaluated the models using single-domain and multi-domain test sets. As a practical outcome of our work, we introduce SAGE(Spell checking via Augmentation and Generative distribution Emulation). It is a library for automatic generative SC that includes a family of pre-trained generative models and built-in augmentation algorithms.Comment: to appear in EACL 202

Text messaging and retrieval techniques for a mobile health information system

Mobile phones have been identified as one of the technologies that can be used to overcome the challenges of information dissemination regarding serious diseases. Short message services, a much used function of cell phones, for example, can be turned into a major tool for accessing databases. This paper focuses on the design and development of a short message services-based information access algorithm to carefully screen information on human immunodeficiency virus/acquired immune deficiency syndrome within the context of a frequently asked questions system. However, automating the short message services-based information search and retrieval poses significant challenges because of the inherent noise in its communications. The developed algorithm was used to retrieve the best-ranked question–answer pair. Results were evaluated using three metrics: average precision, recall and computational time. The retrieval efficacy was measured and it was confirmed that there was a significant improvement in the results of the proposed algorithm when compared with similar retrieval algorithms

Short message service normalization for communication with a health information system

Philosophiae Doctor - PhDShort Message Service (SMS) is one of the most popularly used services for communication between mobile phone users. In recent times it has also been proposed as a means for information access. However, there are several challenges to be overcome in order to process an SMS, especially when it is used as a query in an information retrieval system.SMS users often tend deliberately to use compacted and grammatically incorrect writing that makes the message difficult to process with conventional information retrieval systems. To overcome this, a pre-processing step known as normalization is required. In this thesis an investigation of SMS normalization algorithms is carried out. To this end,studies have been conducted into the design of algorithms for translating and normalizing SMS text. Character-based, unsupervised and rule-based techniques are presented. An investigation was also undertaken into the design and development of a system for information access via SMS. A specific system was designed to access information related to a Frequently Asked Questions (FAQ) database in healthcare, using a case study. This study secures SMS communication, especially for healthcare information systems. The proposed technique is to encipher the messages using the secure shell (SSH) protocol

Performance Analysis of Machine Learning Approaches in Automatic Classification of Arabic Language

Text classification (TC) is a crucial subject. The number of digital files available on the internet is enormous. The goal of TC is to categorize texts into a series of predetermined groups. The number of studies conducted on the English database is significantly higher than the number of studies conducted on the Arabic database. Therefore, this research analyzes the performance of automatic TC of the Arabic language using Machine Learning (ML) approaches. Further, Single-label Arabic News Articles Datasets (SANAD) are introduced, which contain three different datasets, namely Akhbarona, Khaleej, and Arabiya. Initially, the collected texts are pre-processed in which tokenization and stemming occur. In this research, three kinds of stemming are employed, namely light stemming, Khoja stemming, and no- stemming, to evaluate the effect of the pre-processing technique on Arabic TC performance. Moreover, feature extraction and feature weighting are performed; in feature weighting, the term weighting process is completed by the term frequency- inverse document frequency (tf-idf) method. In addition, this research selects C4.5, Support Vector Machine (SVM), and Naïve Bayes (NB) as a classification algorithm. The results indicated that the SVM and NB methods had attained higher accuracy than the C4.5 method. NB achieved the maximum accuracy with a performance of 99.9%

Is text preprocessing still worth the time? A comparative survey on the influence of popular preprocessing methods on Transformers and traditional classifiers

With the advent of the modern pre-trained Transformers, the text preprocessing has started to be neglected and not specifically addressed in recent NLP literature. However, both from a linguistic and from a computer science point of view, we believe that even when using modern Transformers, text preprocessing can significantly impact on the performance of a classification model. We want to investigate and compare, through this study, how preprocessing impacts on the Text Classification (TC) performance of modern and traditional classification models. We report and discuss the preprocessing techniques found in the literature and their most recent variants or applications to address TC tasks in different domains. In order to assess how much the preprocessing affects classification performance, we apply the three top referenced preprocessing techniques (alone or in combination) to four publicly available datasets from different domains. Then, nine machine learning models – including modern Transformers – get the preprocessed text as input. The results presented show that an educated choice on the text preprocessing strategy to employ should be based on the task as well as on the model considered. Outcomes in this survey show that choosing the best preprocessing technique – in place of the worst – can significantly improve accuracy on the classification (up to 25%, as in the case of an XLNet on the IMDB dataset). In some cases, by means of a suitable preprocessing strategy, even a simple Naïve Bayes classifier proved to outperform (i.e., by 2% in accuracy) the best performing Transformer. We found that Transformers and traditional models exhibit a higher impact of the preprocessing on the TC performance. Our main findings are: (1) also on modern pre-trained language models, preprocessing can affect performance, depending on the datasets and on the preprocessing technique or combination of techniques used, (2) in some cases, using a proper preprocessing strategy, simple models can outperform Transformers on TC tasks, (3) similar classes of models exhibit similar level of sensitivity to text preprocessing