6.1 Limitations and future research
We have restricted ourselves in this report to TME as it might impact users of Twitter, but targeted messages can also be sent to users of Google and other search engines (We are also concerned about the possibility that a number of major US tech companies all appear at the moment to share a similar political bias [Our findings in the present study should not be overinterpreted. We have shown, with a sample of 2,133 eligible US voters that biased, targeted tweets can shift opinions and voting preferences in predictable ways with only a small percentage of people showing any awareness that they have been manipulated. The effect proved to be especially large when the content of such tweets was derogatory (content that linguists might call “low-valence and high-arousal” [In a real election people are being subjected to dozens, if not hundreds of different sources of influence that might affect their voting decisions. Other sources of impact could presumably override the impact of biased tweets, and yet there are still, we believe, three reasons why we should be concerned about TME in general and corporation-generated biased tweets in particular. As we noted in our introduction, the bias in TMs is almost always invisible to people, which leads people, mistakenly, to believe that they have made up their own minds. Second, TMs are ephemeral, so unless permanent monitoring systems are in place, we will never know for sure how or even whether TMs are being used to affect people’s opinions and decisions. And third, TMs generated by large online monopolies are inherently noncompetitive; when Twitter, Facebook, or Google deploys biased TMs favoring one candidate, the opposing candidate has no way to counteract them. In other words, online TMs are a uniquely powerful new form of influence.