[1] Johannes Gutenberg Univ Mainz, Dept Law & Econ, Mainz, Germany
[2] German Council Econ Experts, Wiesbaden, Germany
[3] Heinrich Heine Univ Dusseldorf, DICE Dusseldorf Inst Competit Econ, Dusseldorf, Germany
[4] Univ Appl Sci Saarbrucken, Sch Social Sci, Saarbrucken, Germany
[5] Univ Zurich, Dept Econ, Zurich, Switzerland