Disparity Society Theory and Social Stratification Theory: An Attempt to Respond to Challenges by Disparity Society Theory

This paper explores the empirical validity of two important issues recently highlighted by disparity society theory in Japan. The first is income disparity and disparity between regular and non-regular workers. It is clear that social stratification theory has not yet analyzed these issues seriously. It has studied occupations rather than income; it has implicitly assumed that workers have regular jobs. The second issue is recent cross-strata increases in disparity. This paper studies the effect of employment status – regular employment versus non-regular employment – on income by analyzing data produced by Japan’s Social Stratification and Social Mobility Surveys. A regression analysis is applied to the data, with logarithmic income as the dependent variable, and occupation and employment status as independent variables. The result shows that employment status has stronger explanatory power than that of occupation, as argued by discrepancy society theory. To check the empirical validity of the claim that cross-strata disparity is on the increase, this paper compares partial regression coefficients of two regression models using the survey data from 1995 and 2005. The result of the comparison shows that the coefficient of regular employment had become smaller from 1995 to 2005. This means that income disparity between Japanese regular and non-regular workers had shrunken over the decade. It would be risky to argue that income disparity is on the decline based only on this result. A fruitful dialog between disparity society theory and social stratification theory is needed to better comprehend income disparity.