1. Graduate School of Economics and Management, University of Geneva, Campus Biotech, 9 chemin des Mines, 1202 Geneva, Switzerland;
2. Snap Inc., 63 Market St, Venice, CA 90291, USA;
3. Technical University of Munich, Department of Informatics, Chair for Cyber Trust, Boltzmannstrasse 3, 85748 Garching, Germany and
4. School of Information, University of California at Berkeley, 102 South Hall #4600, Berkeley, CA 94720-4600, USA