High Trade Costs and Their Consequences: An Estimated Dynamic Model of African Agricultural Storage and Trade
利用撒哈拉以南非洲42国的月度粮食价格和生产数据，估计并求解农业储存与贸易动态模型，发现贸易成本中位数是世界其他地区的五倍以上，降低这些成本可带来显著福利收益。
Using a new intranational dataset of monthly grain prices and production and a new approach to identify cost parameters, I estimate and solve a dynamic model of agricultural storage and trade covering all 42 countries of continental sub-Saharan Africa. I find median trade costs over five times higher than elsewhere in the world. The potential welfare gains from reducing these costs are substantial, are driven by lower food prices, and can be achieved efficiently by investing in well-targeted trade corridors. A static annual model underestimates trade costs and welfare effects by failing to identify when trade occurs.