Using Supervised Machine Learning and Sentiment Analysis Techniques to Predict Homophobia in Portuguese Tweets


  • Vinicius Gomes Pereira


16/04/2018 - 16:00


Sala da Congregação FGV EMAp (5º andar)


This work studies the identification of homophobic tweets from a natural language processing and machine learning approach. The goal is to construct a predictive model that can detect, with reasonable accuracy, whether a Tweet contains offensive content to LGBT or not. The database used to train the predictive models was constructed aggregating tweets from users that have interacted with politicians and/or political parties in Brazil. Tweets containing LGBT-related terms or that have references to open LGBT individuals were collected and manually classified. A large part of this work is in constructing features that accurately capture not only the text of the tweet but also specific characteristics of the users and language choices. In particular, the uses of swear words and strong vocabulary is a quite strong predictor of offensive tweets. Naturally, n-grams and term weighting schemes were also considered as features of the model. A total of 12 sets of features were constructed. A broad range of machine learning techniques were employed in the classification task: naive Bayes, regularized logistic regressions, feedforward neural networks, extreme gradient boosting (XGBoost), random forest and support vector machines. After estimating and tuning each model, they were combined using voting and stacking. Voting using 10 models obtained the best result, with 89.42% accuracy.

*Texto enviado pelo aluno. 

Membros da banca: 

  • Eduardo Fonseca Mendes (orientador) - FGV/EMAp
  • Renato Rocha Souza (FGV/EMAp)
  • Luiz Paulo Moita Lopes (UFRJ)