Abstract: This article analyzes the ethical discussion focusing on the Facebook emotional contagion experiment published by the Proceedings of the National Academy of Sciences in 2014. The massive-scale experiment manipulated the News Feeds of a large amount of Facebook users and was successful in proving that emotional contagion happens also in online environments. However, the experiment caused ethical concerns within and outside academia mainly for two intertwined reasons, the first revolving around the idea of research as manipulation, and the second focusing on the problematic definition of informed consent. The article concurs with recent research that the era of social media and big data research are posing a significant challenge to research ethics, the practice and views of which are grounded in the pre social media era, and reflect the classical ethical stances of utilitarianism and deontology.
Keywords: Big data; emotional contagion; Facebook; informed consent; manipulation; methodology; privacy; research ethics; social media; user data