The Structure of Intragenerational Mobility

This paper analyzes mobility rates for black and white men using life-history data on intragenerational mobility. Mobility is linked to the process of occupational achievement. It is argued that job mobility is generated by persons' attempts to maximize their status and income. Since opportunities for better jobs will be fewer the higher the occupational achievement already attained, the rate of mobility will depend on time in the labor force. The mathematical formulation of this time dependency is derived from a simple change model for the occupational achievement process. With this formulation, a redefinition of time is possible and job shifts in the redefined time scale can be described by a Poisson process. One component in the formulation of a realistic and theoretically meaningful stochastic model of mobility is then obtained. The empirical analysis indicates that the proposed model describes the observed change in mobility rates over time reasonably well.