Samuel Rosenberg has also argued, the average tenure even for secondary workers is several years, suggesting that at least some secondary workers stay at their jobs for relatively long periods and are not perpetual job-changers. Robert Buchele also found that secondary workers had relatively high tenure. These findings reinforce the view that it is the lack of job security and the ever-present possibility of immediate replacement by others from the reserve army that marks a secondary job. If some secondary workers (especially those studied by Doeringer and Piore) respond to this situation by choosing to change jobs frequently, others (those studied by Rosenberg and Buchele) asses their chances differently and remain at a single job. All secondary workers, however, experience the lack of job protection and the immediate possibility of replacement.
Recent research of Carnoy and Rumberger helped flesh out other aspects of secondary employment. Defined evidence that secondary jobs dead-end employment in the sense that additional experience does not lead to higher earnings. Thus, in their sample the wage profile–the curve showing how much wages rise with increasing age–is flat, showing no wage increase for black secondary workers from the workers until about fifty years of age (thereafter wages tend to fall); in finding is reproduced in both Buchele’s and Osterman’s studies, where labor force experience (or age) contributes so little to earnings that it is statistically insignificant. And David Gordon found that among black males in the secondary market, the age-wage profile is entirely flat, while among primary workers, wages rise with age.
Another characteristics of secondary jobs that is well supported in these studies is the small return to education. Buchele found that for workers with less than a high school education, there was a slight benefit for each year of schooling achieved, but secondary workers got no additional return for any further schooling, although occupational training did help. In Osterman’s sample, the effect of education in increasing earning was four to six times greater for primary workers than for secondary workers; in fact, he return that secondary workers obtained from an extra year of education was so slight that statistically we cannot be sure it is different from zero, and the findings applied to all secondary males, whether white or black. Similar results, though stronger for black secondary workers, were obtained by Gordon and by Carnoy and Rumberger.
Thus, labor market research seems to bear out the conclusion that the secondary market is indeed a distinct market, characterized both by different market outcomes and different market processes. It contains low-paying jobs of casual labor, jobs that provide little employment security or stability and for which the links between one job a worker may hold and the next are slight. These are dead-end jobs offering little opportunity for advancement, requiring few skills. Neither seniority nor education seems to pay off. And since employers have little investment in matching workers and their jobs, they feel free to replace or dismiss workers as their labor needs change.