[1] CERGE EI, Politickych Veznu 7, Prague 11121, Czech Republic
[2] Charles Univ Prague, Inst Econ Studies, Fac Social Sci, Opletalova 1606-26, Prague 11000, Czech Republic
[3] ESSEC Business Sch, 3 Ave Bernard Hirsch, F-95021 Cergy Pontoise, France
[4] THEMA, 3 Ave Bernard Hirsch, F-95021 Cergy Pontoise, France
[5] OECD, Directorate Sci Technol & Innovat, 2 Rue Andre Pascal, F-75016 Paris, France
[6] London Sch Econ, Ctr Econ Performance, Houghton St, London WC2A 2AE, England
[7] World Bank, 1818 H St NW, Washington, DC 20433 USA