CBD LAND VALUES AND MULTIPLE EXTERNALITIES

Generalized spatial models of urban activity emphasize the importance of a land value gradient that declines with distance from the central point within an urban area. Empirical tests of this phenomenon consistently support the theory (Diamond 1980; Chicoine 1981; Asabere and Harvey 1985). However, there has been much less research on the nature of land value gradients within the narrower geographic confines of the Central Business District (CBD) itself. Utilizing a unique data set of actual vacant land transactions, this study empirically explores the pattern of land values within a major metropolitan CBD. A behavioral model of land values is specified and several alternative functional forms for the general model are estimated. These estimates are then compared to estimates of a non-behavioral model that is based on purely spatial relationships, trend surface analysis. A close look at the spatial implications of both models reveals that there are many pitfalls in the analysis of land values within a tightly bound geographic area. In particular, there are inherent statistical problems in utilizing micro data in the confines of a CBD. Also, the confounding influence of street externalities may distort exact locational centrality of the dominant point in the CBD. Finally, care must be taken to prevent the tendency to interpret spatial data beyond the actual spatial confines of the data itself.