Switzerland applies seasonal tariff rate quotas (TRQs) for the import of many fruits and vegetables during the domestic harvest season. We examine how this system affects the relationship between Italian and Swiss tomato prices and test for physical market integration and spatial equilibrium conditions over time. We use detailed, transaction‐based data on trade flows and trade costs and estimate an extended parity bounds model, following Barrett and Li (2002). We confirm that in the summer season, when TRQs are in place, markets are inefficient. While quota holders receive positive rents, the marginal rents for importers without quota shares are negative. This inhibits trade flows above the in‐quota import quantity allowed by TRQs. Hence, despite leading to inefficiencies and creating rents for importers, seasonal TRQs are effective in protecting domestic production against competing imports.

中文翻译：

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季节性关税配额下的市场整合与市场效率

瑞士在国内收成季节对许多水果和蔬菜的进口实行季节性关税配额（TRQ）。我们研究了该系统如何影响意大利和瑞士番茄价格之间的关系，并测试了实物市场整合和一段时间内的空间均衡条件。根据Barrett和Li（2002），我们使用有关交易流量和交易成本的基于交易的详细数据，并估计了一个扩展的平价界限模型。我们确认，在夏季，当有关税配额时，市场效率低下。虽然配额持有人获得正租金，但没有配额份额的进口商的边际租金为负。这会抑制贸易流量超过关税配额所允许的配额内进口数量。因此，尽管导致效率低下并为进口商带来租金，