@article{Mujawamariya:126236,
      recid = {126236},
      author = {Mujawamariya, Gaudiose and Burger, Kees and D'Haese,  Marijke F.C.},
      title = {Behaviour and performance of traders in the gum arabic  supply chain in Senegal: Investigating oligopsonistic  myths.},
      address = {2012},
      number = {1007-2016-79423},
      pages = {55},
      year = {2012},
      abstract = {Farmers face monopsonist/oligopsonist structures in  agricultural or forest products markets because of the  limited choice of traders/buyers. As a consequence, these  farmers and traders alike, in successive transactions along  the supply chain, may get lower prices in selling their  products. This leads to a problem of double (or even  multiple) marginalisation. We investigate oligopsonist  tendencies in the trade of gum arabic, a non-timber forest  product which is widely used as an additive in food and  non-food industries. We compute traders’ shares and a  corresponding Herfindahl index in primary, transport and  wholesale markets of gum arabic in Senegal to analyse the  market concentration; through a gllamm procedure we analyse  determinants of these market shares and finally by a  weighted least square regression, we analyse determinants  of marketing margins of individual traders. The computed  Herfindahl index was found too low to have any influence on  margins and hence oligopsonist powers could not be  confirmed. Instead traders’ margins depend on costs, risk  and uncertainty that they face. Consequently, traders were  not found exploitative; their power is derived from access  to capital and market characteristics.},
      url = {http://ageconsearch.umn.edu/record/126236},
      doi = {https://doi.org/10.22004/ag.econ.126236},
}