a model of iran’s farm-retail marketing margin for beef

high and increasing beef marketing margin leads one to controversy about factors affecting it. this study using the monthly data for the 1998-2005 period to investigate the market power and to estimate how farm and marketing services supplies and retail demand determinants can affect beef marketing margin. the results show that farm, marketing services and retail level prices and thereby marketing margin move together in different ways that depend on whether the determinants that cause movement arise from a shift in retail demand, marketing services supply or farm supply. and also, positive impact of market power beef marketing margin is observed.