The social media services we use can derive immense insight and personal information about us and our moods from the way we use them, and arguably none is more fastidious in that regard than Facebook which harvests immense data on its users.
The secret document was put together by two Australian Facebook execs and includes information about when young people are likely to feel excited, reflective, as well as other emotions related to overcoming fears.
http://www.news.com.au/technology/online/social/leaked-document-reveals-facebook-conducted-research-to-target-emotionally-vulnerable-and-insecure-youth/news-story/d256f850be6b1c8a21aec6e32dae16fd