Funding for this research was provided by:
ETH Foundation through the Risk Center
Vienna Science and Technology Fund (VRG16-005)
Received: 25 August 2017
Accepted: 4 January 2018
First Online: 18 January 2018
Ethics approval and consent to participate
: All data analyzed in this study was publicly available in Twitter. Only explicitly public information was used as ground truth (biographical text, locations) and no private information of any user was predicted as part of this research. This observational study was based only on public archival data and carried no intervention and no interaction with any individual. Thus, this research carries minimum risk and is exempt of the need of consent or of an institutional review.
: The authors declare that they have no competing interests.
: Not applicable.