Exploring Political Ad Libraries for Online Advertising Transparency: Lessons from Germany and the 2019 European Elections

This study investigates the possibilities and limits presented by the newly created ad libraries from Facebook and Google to analyze online political campaigns. We selected Germany as a case study and focused on the months leading up to the 2019 elections to the European Parliament. We identified the political actors that were active advertisers, compared their spending, and contrasted the number of ad impressions with user engagement on their organic online content. From the political ads, we extracted the unique ads and manually analyzed a subsample of them. Furthermore, we explored regional and demographic distributions of users reached by the advertisements and used them as a proxy for the advertisers’ targeting strategies. We also compared the success of the ad campaigns on boosted Facebook posts. We found that even though all the major German political parties engaged in online ad campaigns, they kept their attempts at microtargeting to a minimum. Although their Facebook-sponsored posts were more successful than normal posts, we did not find statistical significance for all the political parties. Interestingly, we noticed that the distribution of users reached by the right-wing party Alternative für Deutschland (AfD) diverges from that of the other parties. Finally, we discuss further challenges for enhancing transparency in online advertising.     «

This study investigates the possibilities and limits presented by the newly created ad libraries from Facebook and Google to analyze online political campaigns. We selected Germany as a case study and focused on the months leading up to the 2019 elections to the European Parliament. We identified the political actors that were active advertisers, compared their spending, and contrasted the number of ad impressions with user engagement on their organic online content. From the political ads, we e...     »