>Facebook only shows some posts algorithmically, and emotionally, they were probably more or less neutral. I'm assuming you mean in aggregate? > They chose to

>Facebook only shows some posts algorithmically, and emotionally, they were probably more or less neutral. I'm assuming you mean in aggregate? > They chose to expose some people to predominantly sad and depressing posts, which is not "what they're already being exposed to" Can you source your "predominantly" here? If their algorithm is operating randomly, it stands to reason that some amount of people will get a "predominantly" negative feed from time to time. So in this sense, some people were unwittingly being exposed to a predominately negative feed. So it seems reasonable to understand the results of this. If their experiment resulted in people seeing negativity far beyond what is a possible outcome from their algorithm, then you might have a point about it being unethical.