Is Facebook to blame for the attacks on refugees in Germany?

The study by Karsten Müller and Carlo Schwarz: Fanning the Flames of Hate: Social Media and Hate Crime, Working Paper Series, University of Warwick No. 373 May 21, 2018 comes to the conclusion: “Our results suggest that social media can act as a propagation mechanism between online hate speech and real-life violent crime.”
First, the authors equate the use of the AFD (Alternative für Deutschland) Facebook page with the use of all right-wing social media pages. “In our setting, the share of a municipality’s population that use the AfD Facebook page is an intuitive proxy for right-wing social media use.” The general local use of local media is identified with the use of the “Nutella” page: “We thus attempt to isolate the local component of social media usage that is uncorrelated with right-wing ideology by drawing on the number of users on the “Nutella Germany” page”.
Jonny Häusler sums up the result on WIRED: “The study comes to the conclusion that there was a significant increase in violence against fugitives in small and large, liberal and conservative, poorer and richer communities if the average Facebook use in these communities was above the national average. In short, “Those who are too much on Facebook become violent against fugitives.”
So by using the “Nutella” Facebook page, you become a beast? Extremely unlikely, but we don’t want to ironize the efforts. It’s difficult enough to investigate the impact of the Internet and social media. But it remains so: correlations do not prove causality. Thus economics professor Tyler Cowen draws a sober balance on MARGINAL REVOLUTION: “As it stands right now, you shouldn’t be latching on to the reported results from this paper.”