Zhang, Mingxia

December, 2002

By: Zhang, Mingxia; Sexton, Richard J.; Alston, Julian M.
This study investigates market conditions when food processor/handler brand advertising, whether undertaken by an investor-owned firm or by a cooperative, will benefit or harm farmers. Addressing this question provides insight into the policy issue of whether and when promotion funds intended to benefit farmers should be used in support of brand advertising. Analysis of a two-stage oligopoly-oligopsony model shows that advertising by an investor-owned firm is most likely to be harmful to farmers when it takes place in a relatively unconcentrated industry and when advertising is relatively more effective at creating brand market power than at increasing total demand.

July, 2000

By: Zhang, Mingxia; Sexton, Richard J.
Exclusive contracts (often called "captive supplies") between processors and farmers are in increasingly important feature of modern agriculture. We study an interesting empirical regulatory occurring in markets that feature both contract and spot exchange: the spot price is inversely related to the incidence of contract use in the market. We use a spatial model and a noncooperative game approach to show that processors can use exclusive contracts to manipulate the spot price in certain situations. Captive supplies in these settings represent geographic buffers that reduce competition among processors. However, in markets where the spatial dimension is less important, captive supplies are ineffective as barriers to competition because firms have incentive to "jump" across a captive supply region to procure the farm product.