Traditional social science models of class groups in the United States are based on economic status and assume that women's economic status derives from association with men, typically fathers or husbands, and that women therefore have more compelling common interest with men of their own economic class than with women outside it. Some feminist social scientists, by contrast, have argued that the basic division in American society is instead based on gender, and that the total female population, regardless of economic status, constitutes a distinct class. Social historian Mary Ryan, for example, has argued that in early-nineteenth-century America the identical legal status of working-class and middle-class free women outweighed the differences between women of these two classes: married women, regardless of their family's wealth, did essentially the same unpaid domestic work, and none could own property or vote. Recently, though, other feminist analysts have questioned this model, examining ways in which the condition of working-class women differs from that of middle-class women as well as from that of working-class men. Ann Oakley notes, for example, that the gap between women of different economic classes widened in the late nineteenth century: most working-class women, who performed wage labor outside the home, were excluded from the emerging middle-class ideal of femininity centered around domesticity and volunteerism.