This migration to more prosperous places saps the Puerto Rican economy of potential, but it is precisely what economists think ought to happen when one region of a larger economy falls on hard times.

人口流向更加富庶的地区，破坏了本地的潜力。这就是大中小区域落难时的情况，跟学家想的一样。

Based on an analysis of infection data, The Economist sees two large zones that could emerge as bubbles, subsuming the smaller ones that are now being formed.

根据对感染数据的分析，《学人》认为有两个大区域形成旅游圈，其中包括正在形成的较小区域。

Economist Brian Jackson is with IHS Economics China Regional Service.

学家 Brian Jackson 就职于 IHS Economics 中国区域服务部。

The phenomenon was first described in a pamphlet by economist William Forster Lloyd in 1833 in a discussion of the overgrazing of cattle on village common areas.

这种现象最初由学家威廉·福斯特·洛伊德于1833年在一本小册子中描述，当时他在讨论村庄公共区域上牛群的过度放牧问题。