What motivates politicians and political parties to shift their positioning on an issue? Focusing on the case of trade policy in countries with advanced economies and plurality electoral systems, I argue that the relative positioning of parties on an existing issue can change even when the preferences of the key actors (voters and politicians) are held constant, and even when party leaders continue to represent the same constituencies. In advanced plurality countries, college-educated voters support free trade, and high-density constituencies are predominantly represented by Left incumbents. As college-educated workers migrate to high-density constituencies in pursuit of higher wages, Left incumbents increasingly embrace free trade, while Right incumbents take more protectionist positions. I provide empirical support for several observable implications of my theory.

中文翻译：

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交易场所、交易平台：贸易政策调整的地理

是什么促使政治家和政党改变他们在某个问题上的立场？着眼于发达经济体和多元化选举制度国家的贸易政策案例，我认为即使关键行为者（选民和政治家）的偏好保持不变，甚至可能改变政党在现有问题上的相对定位，甚至当党的领导人继续代表相同的选区时。在发达的多元化国家，受过大学教育的选民支持自由贸易，高密度选区主要由左翼现任议员代表。随着受过大学教育的工人为了追求更高的工资而迁移到高密度选区，左翼现任者越来越接受自由贸易，而右翼现任者则采取更多的保护主义立场。