The law of one price: a test based on prices for selected inputs in New Zealand agriculture
利用新西兰农业15种投入品的价格数据，检验一价定律是否成立。短期结果不支持一价定律，长期结果好坏参半，提示在建模尤其是政策建模中不应假定一价定律普遍成立。
Abstract The law of one price (LOOP) is an essential foundation of both the pure theory of trade and monetary theory. Strictly speaking, the law relates to prices of individual commodities. However, empirical tests of LOOP have often relied on aggregated data. In this paper, a model is derived and estimated using price data for 15 selected inputs in New Zealand agriculture. The results offer no support for the LOOP in the short run, and the results for the long run are mixed. It may be inappropriate, therefore, to assume that the LOOP holds generally in modelling exercises, particularly when models are used for policy purposes.