This paper provides data resources for low-resource hate speech detection. Specifically, we introduce two different data resources: (i) the HateBR 2.0 corpus, which is composed of 7,000 comments extracted from Brazilian politicians’ accounts on Instagram and manually annotated a binary class (offensive versus non-offensive) and hate speech targets. It consists of an updated version of the HateBR corpus, in which highly similar and one-word comments were replaced; and (ii) the multilingual offensive lexicon (MOL), which consists of 1,000 explicit and implicit terms and expressions annotated with context information. The lexicon also comprises native-speaker translations and its cultural adaptations in English, Spanish, French, German, and Turkish. Both corpus and lexicon were annotated by three different experts and achieved high inter-annotator agreement. Lastly, we implemented baseline experiments on the proposed data resources. Results demonstrate the reliability of data outperforming baseline dataset results in Portuguese, besides presenting promising results for hate speech detection in different languages.

There has been a steep rise in user-generated content on the Web and social media platforms during the last few years. While the ease of content creation allows anyone to create content, at the same time it is difficult to monitor and control the spread of detrimental content. Recent research in natural language processing and machine learning has shown some hope for the purpose. Approaches and methods are now being developed for the automatic flagging of problematic textual content, namely hate speech, cyberbullying, or fake news, though mostly for English language texts. This paper presents an algorithmic approach based on deep learning models for the detection of violent incidents from tweets in the Spanish language (binary classification) and categorizes them further into five classes – accident, homicide, theft, kidnapping, and none (multi-label classification). The performance is evaluated on the recently shared benchmark dataset, and it is found that the proposed approach outperforms the various deep learning models, with a weighted average precision, recall, and F1-score of 0.82, 0.81, and 0.80, respectively, for the binary classification. Similarly, for the multi-label classification, the proposed model reports weighted average precision, recall, and F1-score of 0.54, 0.79, and 0.64, respectively, which is also superior to the existing results reported in the literature. The study, thus, presents meaningful contribution to detection of violent incidents in Spanish language social media posts.

The exponential growth of social media data in the era of Web 2.0 has necessitated advanced techniques for sentiment analysis. While sentiment analysis in monolingual datasets has received significant attention that in code-mixed datasets still need to be studied more. Code-mixed data often contain a mixture of monolingual content (might be in transliterated form), single-script but multilingual content, and multi-script multilingual content. This paper explores the issue from three important angles. What will be the best strategy to deal with the data for sentiment detection? Whether to train the classifier with the whole of the dataset or only with the pure code-mixed subset from the dataset? How much important is the language identification (LID) for the task? If LID is to be done, how, and when will it be used to yield the best performance? We explore the questions in the light of three datasets of Tamil–English, Kannada–English, and Malayalam–English YouTube social media comments. Our solution incorporated mBERT and an optional LID module. We report our results using a set of metrics like precision, recall, $F_1$ score, and accuracy. The solutions provide considerable performance gain and some interesting insights for sentiment analysis from code-mixed data.

In spite of the superior performance deep neural networks have proven in thousands of applications in the past few years, addressing the over-sensitivity of these models to noise and/or intentional slight perturbations is still an active area of research. In the computer vision domain, perturbations can be directly applied to the input images. The task in the natural language processing domain is quite harder due to the discrete nature of natural languages. There has been a considerable amount of effort put to address this problem in high-resource languages like English. However, there is still an apparent lack of such studies in the Arabic language, and we aim to be the first to conduct such a study in this work. In this study, we start by training seven different models on a sentiment analysis task. Then, we propose a method to attack our models by means of the worst synonym replacement where the synonyms are automatically selected via the gradients of the input representations. After proving the effectiveness of the proposed adversarial attack, we aim to design a framework that enables the development of models robust to attacks. Three different frameworks are proposed in this work and a thorough comparison between the performance of these frameworks is presented. The three scenarios revolve around training the proposed models either on adversarial samples only or also including clean samples beside the adversarial ones, and whether or not to include weight perturbation during training.

Individuals with complex communication needs often rely on augmentative and alternative communication (AAC) systems to have conversations and communicate their wants. Such systems allow message authoring by arranging pictograms in sequence. However, the difficulty of finding the desired item to complete a sentence can increase as the user’s vocabulary increases. This paper proposes using BERTimbau, a Brazilian Portuguese version of Bidirectional Encoder Representations from Transformers (BERT), for pictogram prediction in AAC systems. To fine-tune BERTimbau, we constructed an AAC corpus for Brazilian Portuguese to use as a training corpus. We tested different approaches to representing a pictogram for prediction: as a word (using pictogram captions), as a concept (using a dictionary definition), and as a set of synonyms (using related terms). We also evaluated the usage of images for pictogram prediction. The results demonstrate that using embeddings computed from the pictograms’ caption, synonyms, or definitions have a similar performance. Using synonyms leads to lower perplexity, but using captions leads to the highest accuracies. This paper provides insight into how to represent a pictogram for prediction using a BERT-like model and the potential of using images for pictogram prediction.

Intent detection and slot filling are two necessary tasks for natural language understanding. Deep neural models have already shown great ability facing sequence labeling and sentence classification tasks, but they require a large amount of training data to achieve accurate results. However, in many low-resource languages, creating accurate training data is problematic. Consequently, in most of the language processing tasks, low-resource languages have significantly lower accuracy than rich-resource languages. Hence, training models in low-resource languages with data from a richer-resource language can be advantageous. To solve this problem, in this paper, we used pretrained language models, namely multilingual BERT (mBERT) and XLM-RoBERTa, in different cross-lingual and monolingual scenarios. To evaluate our proposed model, we translated a small part of the Airline Travel Information System (ATIS) dataset into Persian. Furthermore, we repeated the experiments on the MASSIVE dataset to increase our results’ reliability. Experimental results on both datasets show that the cross-lingual scenarios significantly outperform monolinguals ones.

Decompounding is an essential preprocessing step in text-processing tasks such as machine translation, speech recognition, and information retrieval (IR). Here, the IR issues are explored from five viewpoints. (A) Does word decompounding impact the Indian language IR? If yes, to what extent? (B) Can corpus-based decompounding models be used in the Indian language IR? If yes, how? (C) Can machine learning and deep learning-based decompounding models be applied in the Indian language IR? If yes, how? (D) Among the different decompounding models (corpus-based, hybrid machine learning-based, and deep learning-based), which provides the best effectiveness in the IR domain? (E) Among the different IR models, which provides the best effectiveness from the IR perspective? This study proposes different corpus-based, hybrid machine learning-based, and deep learning-based decompounding models in Indian languages (Marathi, Hindi, and Sanskrit). Moreover, we evaluate the effectiveness of each activity from an IR perspective only. It is observed that the different decompounding models improve IR effectiveness. The deep learning-based decompounding models outperform the corpus-based and hybrid machine learning-based models in Indian language IR. Among the different deep learning-based models, the Bi-LSTM-A model performs best and improves mean average precision (MAP) by 28.02% in Marathi. Similarly, the Bi-RNN-A model improves MAP by 18.18% and 6.1% in Hindi and Sanskrit, respectively. Among the retrieval models, the In_expC2 model outperforms others in Marathi and Hindi, and the BB2 model outperforms others in Sanskrit.

This paper presents XeraWord, an innovative tool for automatically generating nominal phrases. XeraWord can be used for different tasks, ranging from teaching languages to the creation of examples in lexicography, or even for the development of resources for natural language processing. In this area, Xera was the first experiment, allowing the automatic generation of nominal phrases in three languages: German, French and Spanish. This tool was extended to support other languages, namely, Portuguese and Galician.

We start by presenting the theory behind the development of Xera and its new version, XeraWord, namely, the applied base methodology, and the natural language processing resources used to support it. Then, TraduWord, a tool specifically developed to construct resources for new languages, is presented. This tool allows the semi-automatic translation of the data required for the nominal phrase generation. For this, we discuss its advantages and disadvantages, analysing the quality of the translated resources, as well as the amount of manual work required to validate and correct these resources.

Ambiguity is considered an indispensable attribute of all natural languages. The process of associating the precise interpretation to an ambiguous word taking into consideration the context in which it occurs is known as word sense disambiguation (WSD). Supervised approaches to WSD are showing better performance in contrast to their counterparts. These approaches, however, require sense annotated corpus to carry out the disambiguation process. This paper presents the first-ever standard WSD dataset for the Kashmiri language. The raw corpus used to develop the sense annotated dataset is collected from different resources and contains about 1 M tokens. The sense-annotated corpus is then created using this raw corpus for 124 commonly used ambiguous Kashmiri words. Kashmiri WordNet, an important lexical resource for the Kashmiri language, is used for obtaining the senses used in the annotation process. The developed sense-tagged corpus is multifarious in nature and has 19,854 sentences. Based on this annotated corpus, the Lexical Sample WSD task for Kashmiri is carried out using different machine-learning algorithms (J48, IBk, Naive Bayes, Dl4jMlpClassifier, SVM). To train these models for the WSD task, bag-of-words (BoW) and word embeddings obtained using the Word2Vec model are used. We used different standard measures, viz. accuracy, precision, recall, and F1-measure, to calculate the performance of these algorithms. Different machine learning algorithms reported different values for these measures on using different features. In the case of BoW model, SVM reported better results than other algorithms used, whereas Dl4jMlpClassifier performed better with word embeddings.

Folk culture represents the social, ethnic, and traditional livelihood of people belonging to a certain tribe or community and is important in keeping their culture and tradition alive. The Mizo people are a Tibeto-Burmese ethnic group, native to the Indian state of Mizoram and neighboring regions of Northeast India. Mizo folk culture is an amalgamation of festivity, celebration, liveliness, kinship, brotherhood, and merriment, and above all, preserves the ethnicity of this tribal community that is fundamentally entrenched. Unfortunately, the Mizos are fast giving up their old customs and adopting the new mode of life that is greatly influenced by the western culture. This makes it all the more crucial to preserve the intangible cultural heritage of this ethnic tribe whose folk cultures are vanishing day by day. To the best of our knowledge, this work is the first attempt at preservation and classification of Mizo folk songs. The first part of this paper presents a literature survey on preservation, analysis, and classification of folk songs. The second part presents the methodology for preliminary classification of Mizo folk songs. Three categories of Mizo folk songs—Hunting chants (Hlado), Children’s songs (Pawnto hla), and Elderly songs (Pi pu zai)—are used in this study. A total of 29 acoustic features are used. A long short-term memory network using custom attention layer has been proposed for classification, whose results are compared with four supervised models (Support Vector Machines, K-Nearest Neighbor, Naive Baye’s, and Ensemble). Experimental results from the proposed model are promising, with an implication of scope for future research in acoustic analysis and classification of Mizo folk songs using recent unsupervised methods.

Sarcasm detection research in the Bengali language so far can be considered to be narrow due to the unavailability of resources. In this paper, we introduce a large-scale self-annotated Bengali corpus for sarcasm detection research problem in the Bengali language named ‘Ben-Sarc’ containing 25,636 comments, manually collected from different public Facebook pages and evaluated by external evaluators. Then we present a complete strategy to utilize different models of traditional machine learning, deep learning, and transfer learning to detect sarcasm from text using the Ben-Sarc corpus. Finally, we demonstrate a comparison between the performance of traditional machine learning, deep learning, and transfer learning models on our Ben-Sarc corpus. Transfer learning using Indic-Transformers Bengali Bidirectional Encoder Representations from Transformers as a pre-trained source model has achieved the highest accuracy of 75.05%. The second-highest accuracy is obtained by the long short-term memory model with 72.48% and Multinomial Naive Bayes is acquired the third highest with 72.36% accuracy for deep learning and machine learning, respectively. The Ben-Sarc corpus is made publicly available in the hope of advancing the Bengali Natural Language Processing Community. The Ben-Sarc is available at https://github.com/sanzanalora/Ben-Sarc.

Most existing discourse annotation guidelines have focused on the English language. As a result, there is a significant lack of research and resources concerning computational discourse-level language understanding and generation for other languages. To fill this relevant gap, we introduce the first discourse annotation guideline using the rhetorical structure theory (RST) for low-resource languages. Specifically, this guideline provides accurate examples of discourse coherence relations in three romance languages: Italian, Portuguese, and Spanish. We further discuss theoretical definitions of RST and compare different artificial intelligence discourse frameworks, hence offering a reliable and accessible survey to new researchers and annotators.