Ice(berg) Transport Costs
利用19世纪波士顿全球冰贸易数据，发现实际冰山运输成本中附加成本占比最大，且运输存在规模经济，挑战了现代贸易模型中常用的冰山运输成本假设。
Abstract Iceberg transport costs are a key ingredient of modern trade and economic geography models. Using detailed information on Boston’s nineteenth-century global ice trade, we show that the cost of shipping the only good that truly melts in transit is not well-proxied by this assumption. Additive cost components account for the largest part of per unit ice(berg) transport costs in practice. Moreover, the physics of the melt process and the practice of insulating the ice in transit meant that shipping ice is subject to economies of scale. This finding supports, from an unexpected historical angle, recent efforts to incorporate more realistic features of the transportation sector in trade and economic geography models.