The internet is currently a fury on Facebook's paper where they spent 1 week in 2012 an manipulated 0.1% of their users feeds to have them see more positive or more negative than average posts, and see what they produced in return. And they published the results here. A very solid summary at the Atlantic.
This outrage seems a little odd, in contrast to the Freemium game explosion, which is all about being as brutally manipulative as possible to make you buy in app upgrades. Candy Crush basically is actively exploiting the same human weaknesses that creates gambling addiction. If we want to talk about ethics in computing right now, Freemium is something we need to have a very serious conversation about.
The study highlights how your filter bubble impacts your mood. If you are exposed to more positive content, you end up more positive. If you are exposed to more negative content, you end up more negative. Not by huge margins, but by noticable ones. Who you are is impacted by what you emotionally ingest. It shouldn't be a surprising idea, but it does take something like Facebook to be able to measure the effect with enough controls to make sure it's real.
If seeing a few minutes a day of more positive or negative content impacts your mood enough to get a reaction out of you, what else impacts it? Home; Work; Friends; Media. And what hacks can you do to impact it yourself.