A Technique of Urbanization Measurement

Abstract

Urbanization has today brought about the increasing concentration of population in large cities. Under these conditions, a new technique of measurement of urbanization is required instead of the former way, from the viewpoint of international comparisons of urbanization. That is to say that a method of measuring which can express the differences between various sizes of city in order to reflect the trend of concentration of population in large cities should be adopted. In this respect, this new method of measuring is different from that of the degree of urbanization which has been used widely. Jack P. Gibbs was the first scholar who proposed this new kind of method of measuring urbanization ( Su=ΣXY, X: proportion of the city population in each size-class and over to the total city population, Y: proportion of the city population in each size-class and over to the total population ). The present author proposes to Improve Glbbs's formula as follows: Su=Σ^^n_<i=1>RiXi Su: indix of the scale of urbanization Ri: rank number (cumulative index) of each size-class Xi: proportion of urban population of each size-class to the total population of a country The appropriateness of the above "index of the scale of urbanization" was tested by the author by comparing it with the degree of urbanization. The degree of change is shown more strikingly in the "Index of the scale of urbanization" than in the degree of urbanization (Fig. 1). And this shows nothing less than the trend of concentration of people in large cities, because the differences of various city size-classes are reflected in the "index of the scale of urbanization". Furthermore, the "index of the scale of urbanization" is related more closely to the size of population of the country than the degree of urbanization (Figs. 2 and 3). As a result, it may be said that the "index of the scale of urbanization" is more useful for measuring the urbanization of a country than the degree of urbanization. In this proposal of an "Index of the scale of urbanization", the important finding is as follows: Urbanization advances gradually to a stable condition in accordance with the development of the national economy, and the subsequent change in population composition is represented by a function of the size of population of a country and the scale of urbanization. This finding was drawn from the evidence that there is a closer relationship between the "index of the scale of urbanization" and the size of population in the economically advanced countries than in the developing ones (Fig. 4). Accordingly, the country with a large population cannot be said to have a large scale of urbanization until the economy is firmly established.