THE EMPIRICAL STRUCTURE OF URBAN SYSTEMS: THE LONDON, ONTARIO, EXAMPLE

S ince the early 1950s there have been numerous studies which have attempted to determine the hierarchical structure of urban-place systems. Although Harris and Ullman identified three general city-forming functions, namely central place, transportation, and specialized, most urban-place system studies since have been based on a measure of the central-place function. Pred emphasizes the problem in his recent work, City Systems in Advanced Economies. He used the term "city systems" because his study is of the complete system and not just the central-place portion of the system. I chose for this study the term "urban-place system" for the same reason, but used "urban-place" rather than "city" because the system contains towns, villages, and hamlets as well as cities.