Informal housing, spatial structure, and city compactness
构建了一个包含正规与非正规住房部门的单中心城市模型，发现非正规住房随距市中心距离增加而增多，导致城市空间扩张、建筑高度降低。
Abstract This paper develops a monocentric city model with a formal and an informal sector in the housing industry. While formal developers build houses renting land from landowners, informal developers use land for free. However, informal developers must incur defensive expenditures to avoid government intervention. In equilibrium, at any distance of the central business district (CBD), informal developers use land until the value of the marginal productivity of land equals the defensive expenditures per unit of land. The model shows the land allocated to produce short informal (tall formal) buildings increases (decreases) with distance to the CBD. Thus, the model introduces a new source of spatial variation of building height. The model also shows that a higher level of informal housing increases the spatial size of a city and reduces the height of its buildings.