Gradients of metropolitan dominance in turkey: Alternative models

The dominance or influence of metropolitan centers in the developing country of Turkey, as measured by gradients of population characteristics (population density, percent urban, sex ratio, percent over five years of age, and percent literate) by distance from the nearest metropolitan center for 1960 and 1965, is found to decrease sharply from the central zone to the next zone (25–49 kilometers from the center), and then change very little with increasing distance from the center, for both urban and rural populations. None of several alternative mathematical models describes the form of the influence of metropolitan centers on the population characteristics of their hinterlands very well, but the best fitting models suggest that population density declines by distance according to an exponential function to the base e, percent urban declines according to a function to the one-fourth power, sex ratio declines for about 100 kilometers and then increases according to a quadratic function, and percent under six years increases and percent literate declines according to a linear function. These results suggest that dominance of a metropolitan center over its hinterland beyond 25 or 50 kilometers in Turkey is not very strong, possibly because of the relatively poorly developed transportation and communication systems. Although metropolitan dominance in Turkey in 1960 and 1965 seems to diminish more sharply with distance and to extend less far from the metropolitan center than in developed countries or than it may as Turkey develops economically and technologically in the future, additional comparative data over time in Turkey and in developed countries at the same time are needed for a rigorous test of this apparent finding.