“…Very often, it is dif® cult to ® nd up-to-date data, especially in a fast-growing metropolis. When data are available, the changing urban spatial structure is investigated through the calibration of regression models which attempt to explain the observed land values, housing values or distribution of ® rms with a number of independent variables (Erickson, 1986;Peiser, 1987;Heikkila et al, 1989;McDonald and McMillen, 1990;Shukla and Waddell, 1991). For example, Erickson ® nds that land costs, transport costs, local market growth and the effects of agglomeration and competition are important factors in land development.…”