700,000 Facebook users were put into an experiment that may have altered their emotions. The participants did not give consent and the study was not subject to third-party ethical oversight.
For one week in January of 2012, approximately 700,000 Facebook users were placed in an experiment to study emotional contagion, the extent to which a person’s emotions are impacted by the emotions of the people they interact with. I’ve discussed this experiment in Chapter 4, but I’ll review it again now. Participants in the Emotional Contagion experiment were put into four groups: a “negativity reduced” group, for whom posts with negative words (e.g., sad) were randomly blocked from appearing in the News Feed; a “positivity reduced” group for whom posts with positive words (e.g., happy) were randomly blocked; and two control groups. In the control for the “negativity reduced” group, posts were randomly blocked at the same rate as the “negativity reduced” group but without regard to the emotional content. The control group for the “positivity reduced” group was constructed in a parallel fashion. The researchers found that people in the positivity-reduced condition used slightly fewer positive words and slightly more negative words, relative to the control condition. Likewise, they found that people in the negativity-reduced condition used slightly more positive words and slightly fewer negative words. Thus, the researchers found evidence of emotional contagion (Kramer, Guillory, and Hancock 2014); for a more complete discussion of the design and results of the experiment see Chapter 4.
Just days after this paper was published in Proceedings of the National Academy of Sciences, there was an enormous outcry from both researchers and the press. Outrage around the paper focused on two main points: 1) participants did not provide any consent beyond the standard Facebook terms-of-service and 2) the study had not undergone third-party ethical review (Grimmelmann 2015). The ethical questions raised in this debate caused the journal to quickly publish a rare “editorial expression of concern” about the ethics and ethical review process for the research (Verma 2014). In subsequent years, this experiment has continued to be a source of intense debate and disagreement, and the criticism of this experiment may have had the unintended effect of driving this kind of research into the shadows (Meyer 2014). That is, some have argued that companies have not stopped running these kinds of experiments, they have merely stopped talking about them in public. This debate may have also lead to the creation of an ethical review process for research at Facebook (Hernandez and Seetharaman 2016; Jackman and Kanerva 2016).