Grain price adjustment asymmetry: the case of cowpea in Ghana

Patterns in price adjustment in response to information are important to market practitioners. This study looks at cowpea real wholesale price adjustment patterns in Bolgatanga, Wa, Makola and Techiman markets in Ghana. Using Techiman as the central market, a threshold autoregressive test for asymmetric price adjustment rejected the null hypothesis of symmetric adjustment for only the Bolgatanga-Techiman price series. An autoregressive conditional heteroskedastic regression indicates that wholesalers in Bolgatanga market respond differentially to price signals from Techiman than those in the other two markets. This suggests that policies targeting cowpea traders must recognize the differential responses by wholesalers to information