A Comparison of Classical Versus Deep Learning Techniques for Abusive Content Detection on Social Media Sites

The automated detection of abusive content on social media websites faces a variety of challenges including imbalanced training sets, the identification of an appropriate feature representation and the selection of optimal classifiers. Classifiers such as support vector machines (SVM), combined with bag of words or ngram feature representation, have traditionally dominated in text classification for decades. With the recent emergence of deep learning and word embeddings, an increasing number of researchers have started to focus on deep neural networks. In this paper, our aim is to explore cutting-edge techniques in automated abusive content detection. We use two deep learning approaches: convolutional neural networks (CNNs) and recurrent neural networks (RNNs). We apply these to 9 public datasets derived from various social media websites. Firstly, we show that word embeddings pre-trained on the same data source as the subsequent classification task improves the prediction accuracy of deep learning models. Secondly, we investigate the impact of different levels of training set imbalances on classifier types. In comparison to the traditional SVM classifier, we identify that although deep learning models can outperform the classification results of the traditional SVM classifier when the associated training dataset is seriously imbalanced, the performance of the SVM classifier can be dramatically improved through the use of oversampling, surpassing the deep learning models. Our work can inform researchers in selecting appropriate text classification strategies in the detection of abusive content, including scenarios where the training datasets suffer from class imbalance

Abusive Language Detection in Online Conversations by Combining Content-and Graph-based Features

In recent years, online social networks have allowed worldwide users to meet and discuss. As guarantors of these communities, the administrators of these platforms must prevent users from adopting inappropriate behaviors. This verification task, mainly done by humans, is more and more difficult due to the ever growing amount of messages to check. Methods have been proposed to automatize this moderation process, mainly by providing approaches based on the textual content of the exchanged messages. Recent work has also shown that characteristics derived from the structure of conversations, in the form of conversational graphs, can help detecting these abusive messages. In this paper, we propose to take advantage of both sources of information by proposing fusion methods integrating content-and graph-based features. Our experiments on raw chat logs show that the content of the messages, but also of their dynamics within a conversation contain partially complementary information, allowing performance improvements on an abusive message classification task with a final F-measure of 93.26%

Abusive Text Detection Using Neural Networks

eural network models have become increasingly popular for text classification in recent years. In particular, the emergence of word embeddings within deep learning architectures has recently attracted a high level of attention amongst researchers. In this paper, we focus on how neural network models have been applied in text classification. Secondly, we extend our previous work [4, 3] using a neural network strategy for the task of abusive text detection. We compare word embedding features to the traditional feature representations such as n-grams and handcrafted features. In addition, we use an off-the-shelf neural network classifier, FastText[16]. Based on our results, the conclusions are: (1) Extracting selected manual features can increase abusive content detection over using basic ngrams; (2) Although averaging pre-trained word embeddings is a naive method, the distributed feature representation has better performance to ngrams in most of our datasets; (3) While the FastText classifier works efficiently with fast performance, the results are not remarkable as it is a shallow neural network with only one hidden layer; (4) Using pre-trained word embeddings does not guarantee better performance in the FastText classifie

Abusive Text Detection Using Neural Networks

Neurall network models have become increasingly popular for text classification in recent years. In particular, the emergence of word embeddings within deep learning architecture has recently attracted a high level of attention amongst researchers

Toxicité et sentiment : comment l'étude des sentiments peut aider la détection de toxicité

La détection automatique de contenu toxique en ligne est un sujet très important aujourd’hui. Les modérateurs ne peuvent filtrer manuellement tous les messages et les utilisateurs trouvent constamment de nouvelles façons de contourner les filtres automatiques. Dans ce mémoire, j’explore l’impact que peut avoir la détection de sentiment pour améliorer trois points importants de la détection automatique de toxicité : détecter le contenu toxique de façon plus exacte ; rendre les filtres plus difficiles à déjouer et prédire les conversations les plus à risque. Les deux premiers points sont étudiés dans un premier article, où l’intuition principale est qu’il est plus difficile pour un utilisateur malveillant de dissimuler le sentiment d’un message que certains mots-clés à risque. Pour tester cette hypothèse, un outil de détection de sentiment est construit, puis il est utilisé pour mesurer la corrélation entre sentiment et toxicité. Par la suite, les résultats de cet outil sont utilisés comme caractéristiques pour entraîner un modèle de détection de toxicité, et le modèle est testé à la fois dans un contexte classique et un contexte où on simule des altérations aux messages faites par un utilisateur tentant de déjouer un filtre de toxicité. La conclusion de ces tests est que les informations de sentiment aident à la détection de toxicité, particulièrement dans un contexte où les messages sont modifiés. Le troisième point est le sujet d’un second article, qui a comme objectif de valider si les sentiments des premiers messages d’une conversation permettent de prédire si elle va dérailler. Le même outil de détection de sentiments est utilisé, en combinaison avec d’autres caractéristiques trouvées dans de précédents travaux dans le domaine. La conclusion est que les sentiments permettent d’améliorer cette tâche également.Automatic toxicity detection of online content is a major research field nowadays. Moderators cannot filter manually all the messages that are posted everyday and users constantly find new ways to circumvent classic filters. In this master’s thesis, I explore the benefits of sentiment detection for three majors challenges of automatic toxicity detection: standard toxicity detection, making filters harder to circumvent, and predicting conversations at high risk of becoming toxic. The two first challenges are studied in the first article. Our main intuition is that it is harder for a malicious user to hide the toxic sentiment of their message than to change a few toxic keywords. To test this hypothesis, a sentiment detection tool is built and used to measure the correlation between sentiment and toxicity. Next, the sentiment is used as features to train a toxicity detection model, and the model is tested in both a classic and a subversive context. The conclusion of those tests is that sentiment information helps toxicity detection, especially when using subversion. The third challenge is the subject of our second paper. The objective of that paper is to validate if the sentiments of the first messages of a conversation can help predict if it will derail into toxicity. The same sentiment detection tool is used, in addition to other features developed in previous related works. Our results show that sentiment does help improve that task as well