Since the 2016 election, the topic of Facebook advertisements and their effect on voting has been widely discussed and debated. But a new study from the University of Warwick, ETH Zurich and the University of Carlos III in Madrid takes a deeper look at the effects that micro-targeted political ads on social media, specifically Facebook, had on the 2016 election.

The Trump campaign is believed to have spent $44 million on Facebook ads alone during the election, reportedly with 175,000 different political ads on the social media site in the months leading up to the election. Likewise, the Clinton campaign spent $28 million on Facebook ads. Both sides saw a lot of potential for advertising on social media, but just how effective was this method at changing voter’s minds?

According to the new study, social media campaigns were fairly effective. The study tested the effect of micro-targeted political ads on social media. Online campaigns used Facebook’s profiling tools to reach their targeted audiences based on factors such as gender, location and outward political allegiance.

The study showed that Trump-related ads on Facebook were effective at persuading undecided voters to vote Republican. They were also effective at encouraging Republican voters to go out to the polling booth. The study also found that people who use Facebook regularly and people who rely on Facebook for their daily news were the most affected by political ads. It also discovered that Facebook users who do not have a college-level education were persuaded by the ads.

Dr. Michela Redoano, associate professor in the University of Warwick Department of Economics said, "Digital campaigning is much cheaper than campaigns in traditional media also thanks to the exploitation of social networks, it is easily accessible, and it is virtually free of regulation. Thanks to predictive analytics, companies like Facebook offer a toolkit for targeting voters at an extremely granular level based on their previous online behavior. These online campaign channels are potentially very powerful political instruments. It is therefore vital that we understand how political campaigns on social media work, their impact on voter behavior, and, ultimately, on election results."

Dr. Federica Liberini from ETH Zurich, said, "Our research allowed us to build a simple measure for tracking the intensity of political campaigns conducted on social media. In the context of the 2016 U.S. Presidential elections, we find that political micro-targeting was particularly effective when based on ideology and gender or educational level, and much less so when based on race or age. Our results show that social media effectively empowered politicians to influence key groups of voters in electoral races, and it is further evidence that recent political outcomes, such as Brexit and the election of President Trump, might be largely due to the use of data analytics.”

Dr. Antonio Russo, also from ETH Zurich, added, "Our finding that Facebook had a strong effect on turnout suggests that social media has great potential for stimulating the political participation of people who would otherwise have lost interest in politics. In a world where confidence in democracy is dwindling, I believe this is good news. However, we still have much to learn about whether the information that voters are exposed to on social media really helps them make informed choices."

Dr. Angel Cuevas and Dr. Ruben Cuevas from the University Carlos III in Madrid commented, "In this line, we have already used Facebook data to measure the gender divide worldwide and we are using in a still ongoing work to create a new methodology to measure culture. We would also like to highlight that this data is serving to promote fruitful multidisciplinary collaboration between computer scientists and social scientists."

The paper is titled Politics in the Facebook Era: Evidence from the 2016 US Presidential Elections.