Urban Evolutions: The Fast, the Slow, and the Still
利用法国和美国数据，研究产业在城市间的快速迁移、城市在等级体系中的缓慢升降以及城市规模分布的稳定特征，并构建模型复现这三种现象。
With the use of French and US data, new and systematic evidence is provided about the rapid location changes of industries across cities (the fast). Cities are also slowly moving up and down the urban hierarchy (the slow), while the size distribution of cities is skewed to the right and very stable (the still). The model proposed here reproduces these three features. Small, innovation-driven shocks lead to the churning of industries across cities. Then, cities slowly grow or decline following net gains or losses of industries. These changes occur within a stable distribution. The quantitative implications of the model are also explored.