Demographic Models of Internal Labor Markets.

This research was supported in part by a grant from the National Science Foundation (SES 80-17884). This paper expands the scope of organizational demography to include two populations, the population of workers and the population of jobs. White's (1970) vacancy chain model is extended, and several new properties for vacancy chains are developed. The latter pertain to interpreting the chain reactions of vacancies in terms of person moves (promotions, demotions, transfers, and hires), analytically separating the effects of internal staffing and external hiring, and separately estimating vacancy behavior for new and old jobs, when job evolution is significant. The extensions beyond vacancy chains pertain to additional social structures, most notably job grade distributions, multiple grade ratios and organizational Venturi tubes. Job distributions, vacancy chains, and managerial staffing and hiring practice are combined to form a compound structure of multiple grade ratios. These multiple grade ratios are then used to construct organizational Venturi tubes, which indicate the relative career chances over the full organizational hierarchy. Data for the analyses were derived from three internal labor markets (two managerial, one professional) and ranged from two to five decades.e