Coffee, Tanzania's largest export crop, contributes about 115 dollars to the country 's export earnings. About 95 percent of coffee is produced by some 400,000 smallholders on average plots of 1-2 hectares. Most do not use purchased inputs such as chemicals and fertilizers. Before 1990 all...

Mathematical programming models are widely used in agricultural sector analysis. Lack of micro-level data and computational reasons necessitate aggregation of individual producers into regional representative units when working at sectoral level. This usually leads to unrealistic and extreme...