A non-parametric Approach to Specifying Changes of Preferences German Consumers for the Iranian and U.S. Pistachios

Document Type : Research Paper


1 Professor of Agricultural Economics, University of Tehran, College of Agriculture and Natural Resources, Tehran, Iran

2 Ph.D. Student of Agricultural Economics, University of Tehran, College of Agriculture and Natural Resources, Karaj, Iran


Observing aflatoxin in Iranian pistachio from time to time and continuing substitution of U.S. pistachios instead of the Iranian one in the German market suggests that changes in the preferences of German consumers may have occurred against Iran's pistachios. The present study seeks to test this hypothesis. Given that, data on imports of pistachios from Iran and the United States during the period of 1988-2015 have been examined using a nonparametric approach based on the weak and strong axiom of revealed preferences. In addition, the K-W test has been used to test the significance of the observed violations. Results showed that, structural changes have occurred in the preferences of German consumers against Iranian pistachios. Additionally, the main reason for the observed preference changes roots in the health considerations by the German consumers. Hence, it would be difficult for Iranian exporters to regain the German market. Ensuring the continuity of healthy pistachio production and its guarantee by the official health authorities may help to restore the German market to Iranian pistachio exporters.


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