Multi-label text classification on unbalanced Twitter with monolingual model and hyperparameter optimization for hate speech and abusive language detection

The increase in hate speech and abusive language on social media leads to uncomfortable interactions among users. Many datasets available publicly that address hate speech and abusive language are not balanced, particularly those from Indonesian Twitter. To develop a more effective classification model that also considers minority classes, we needed to optimize the hyperparameters of a monolingual model, use four different data preprocessing scenarios, and improve the treatment of slang words. We assessed the model's effectiveness by its accuracy, achieving 81.38%. This result came from optimizing hyperparameters, processing data without stemming and removing stop words, and enhancing the slang word data. The optimal hyperparameters were a learning rate of 4e-5, a batch size of 16, and a dropout rate of 0.1. However, using too much dropout can decrease the model’s performance and its ability to predict less common categories, such as physical- and gender-related hate speech.