Sentiment analysis identifies terms or entities about which a person has “an overall majority opinion which is not shared by a different class,” for example, a particular
political figure who is seen as divisive. The critical function of sentiment analysis is to take an opinion expressed online and classify it as expressing a positive, negative, or neutral attitude. Sentiment analysis can be employed across a wide range of topics, from the state of American political discourse to the support for ISIS in the Middle East. However, some researchers caution that an overreliance on sentiment analysis risks overstating the role of social media in representing a larger societal voice, rather than representing the percentage of a given population that is online and engaged on a topic.