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Metropolitan Fragmentation and Suburban Homogeneity

The behavioural models which underlie social scientists' views of metropolitan population distribution assume or imply strong preferences for socio-economic homogeneity within a geographic area . A derivative of this behavioural assumption is a widespread belief that metropolitan fragmentation has facilitated the achievement of homogeneity. The literature on the suburbs and on intra-metropolitan population movement and distribution devotes considerable attention to the consequences of this assumed social and economic similarity within local political boundaries and the extensive differentiation across these boundaries . In this paper, having tried to devise a practical definition of homogeneity, we look at the evidence for the metropolitan areas of Pennsylvania . Our major finding is that the extent of homogeneity actually achieved has been more limited than is generally believed . Despite the considerable emphasis on income homogeneity in the social science literature, we find little evidence for it . However, the absence of realised homogeneity casts little light on the validity of the underlying behavioural assumption that a desire to live with others of similar background and circumstance is an important feature of social life . Indeed, such desires may be fundamental but their realisation is limited by a number of complicating factors . Section 2 reviews some of the social science and social policy literature in which the concept of homogeneity, whether realised or as a descriptive tendency, is a central feature of the discussion . Section 3 proposes a measure of homogeneity which corresponds to the theoretical concept implicit in most discussions . Section 4 presents the results of applying our measure to the 1970 Census data for towns within the metropolitan areas of Pennsylvania .1 We have chosen to look closely at the metropolitan areas in one state because