Comment by ceejayoz

There are lots of examples of this.

https://www.theguardian.com/news/2018/mar/18/facebook-cambri...

> He was hired to work at Facebook as a quantitative social psychologist around November 2015, roughly two months after leaving GSR, which had by then acquired data on millions of Facebook users.

https://venturebeat.com/2014/06/07/exclusive-to-sell-ads-in-...

> Corey has been working as a quantitative researcher at Facebook since last summer. His growth research team has “two sociologists and a manager trained in communications with a sociologist as an advisor,” according to an article he published early this year. The team helps expand Facebook to developing countries. Corey uses R-based software stack, collects data via Hive and uses a few other coding languages to do his job.

https://www.theatlantic.com/technology/archive/2014/06/every...

> We now know that’s exactly what happened two years ago. For one week in January 2012, data scientists skewed what almost 700,000 Facebook users saw when they logged into its service. Some people were shown content with a preponderance of happy and positive words; some were shown content analyzed as sadder than average. And when the week was over, these manipulated users were more likely to post either especially positive or negative words themselves.

> This tinkering was just revealed as part of a new study, published in the prestigious Proceedings of the National Academy of Sciences. Many previous studies have used Facebook data to examine “emotional contagion,” as this one did. This study is different because, while other studies have observed Facebook user data, this one set out to manipulate it.