Bounding Analyses of Mobility Effects

• In Event: 2246 - Social Mobility and Intergenerational Relationships

Abstract

In recent years there has been an increase in the number of quantitative studies examining the
consequences of individual-level socioeconomic mobility. Nearly all of these studies in sociology
and demography have used Sobel’s (1981; 1985) diagonal reference model. In this paperwe
examine the mathematical properties of the Sobel model. We showthat, under plausible values
of mobility effects, the diagonal reference model tends to generate results that implicitly force
the mobility linear effect to zero. As such, the model has little advantage over Duncan’s square
additive model, which has been abandoned for similar reasons. We conclude with a caution to
researchers interested in using the diagonal reference model for estimating the consequences
of social mobility. The resulting estimated mobility effects are, in part, an artifact of the model
and should be interpreted judiciously. In general,when using the technique researchers should
decompose the mobility parameters using orthogonal projection, which will reveal the potentially
strong assumptions underlying the model.

Authors

• Ethan Fosse, University of Toronto

• Fabian T. Pfeffer, University of Michigan