1. School of Economics, University of Nottingham, University Park, Nottingham, NG7 2RD, UK (email: )
2. African Studies Centre, University of Leiden, Wassenaarseweg 52, 2333 AK Leiden, the Netherlands (email: )
3. School of Business and Economics, Vrije Universiteit Amsterdam, De Boelelaan 1105, 1081 HV Amsterdam, the Netherlands (email: )
4. School of International Development and Centre for Behavioural and Experimental Social Science (CBESS) at the University of East Anglia, Norwich NR4 7TJ, UK (email: )
5. Markets, Trade and Institutions Division, International Food Policy Research Institute, 1201 Eye Street, NW, Washington, DC 20005 (email: )