Automation in the Automobile Industry: Some Consequences for In-Plant Social Structure

correlation of -.39 with mean rent and the corresponding figure for the fertility ratio was -.47. In 1950 the coefficients of correlation for these two indices shifted to +.17 and +.12, respectively. When correlated with median grade completed these two indices showed a negative relationship for both 1940 and 1950, but the coefficients were generally much lower in 1950. In conclusion, while certain generalizations concerning the significance of socio-economic status in the ecological structure of the American city obtained for both 1940 and 1950, other generalizations seem to reflect increasing variability. It is suggested that further consideration of the socio-economic status aspect of the ecology of the American city might be studied in terms of a series of specific continua rather than on the basis of a single broad dimension. This suggestion should not be construed as inconsistent with the present emphasis on the socio-economic status dimension. The disassociation of measures pertaining to the foreign-born population, males, fertility, children, and to the older population, from measures of income, occupation, and education indicates possible directions which may be followed in the further analysis of the problem. These changes may reflect the decreasing importance of the foreign-born population, greater homogeneity of the sex ratio, a movement of older persons to central sections of cities, and a closer relationship between fertility and suburban residence than socio-economic status per se. An additional continuum is suggested for the Negro population, which has become associated more closely with the socio-economic cluster of measures. Whether or not such dimensions can be observed in the measures used in this study is unknown. However, this interpretation of the structure of the measures and dimensions is basically consistent with the dimensions of city structure described by Shevky and Tryon and their associates.3 As the next step in attempting to clarify some of the problems raised in this paper, including the possible derivation of additional dimensions pertaining to the ecological structure of the large urban community, the authors are planning to apply factor analysis techniques to the basic data.