[1] Trier Univ, Chair Management, Univ Ring 15, D-54296 Trier, Germany
[2] Erasmus Univ, Sch Econ, Erasmus Inst Management, Dept Appl Econ, POB 1738, NL-3000 DR Rotterdam, Netherlands
[3] Saarland Univ, ZeMA gGmbH, Gewerbepk Eschberger Weg 46,Geb 9, D-66121 Saarbrucken, Germany
[4] Trier Univ, Dept Econ, Univ Ring 15, D-54296 Trier, Germany
[5] Trier Univ, Dept Psychol, Univ Ring 15, D-54296 Trier, Germany