The document summarizes research on using machine learning techniques to analyze sentiment and detect stress levels from text data on Reddit. It discusses prior work applying preprocessing methods like tokenization, stemming and stop word removal. Feature extraction techniques explored include n-grams, LIWC, LDA and TF-IDF. Supervised learning classifiers tested were SVM, logistic regression, random forest, AdaBoost and neural networks. The best performing model was logistic regression with domain-specific word embeddings, achieving an F1 score of 79.80% for stress detection.