This document describes a study that aims to (1) explore the relationship between life satisfaction and depression on social media by analyzing tweets, and (2) develop a predictive model to detect depressed posts on social media. The researchers collected tweets containing words related to depression and preprocessed the data. They then trained several predictive models and evaluated them using metrics like confusion matrix. The best model showed a negative correlation between life satisfaction and depression and was able to accurately detect depressed posts on social media.