Measuring global economic activity
指出基于航运成本的世界经济活动代理指标存在归一化问题，并评估了该指标及其他替代指标，发现基于世界工业生产的指标更能反映全球实际经济活动。
Summary A number of economic studies have used a proxy for world real economic activity derived from shipping costs. This measure turns out to depend on a normalization that has substantive consequences, of which users of the index had been unaware prior to this paper. This paper further evaluates this and alternative measures in terms of treatment of trends, coherence with world output, and correlation with commodity prices. I conclude that measures derived from world industrial production offer a better indicator of global real economic activity.