[1] Charles Univ Prague, Inst Econ Studies, Fac Social Sci, Opletalova 26, Prague 11000, Czech Republic
[2] Univ Econ, Dept Banking & Insurance, Fac Finance & Accounting, Namesti Winstona Churchilla 4, Prague 13067, Czech Republic
[3] Univ Calif Berkeley, Dept Agr & Resource Econ, 207 Giannini Hall, Berkeley, CA 94720 USA