Stepping-stone mobility

People at the top of an occupational ladder earn more partly because they have spent time on lower rungs, where they have learned something. But what precisely do they learn? There are two contrasting views: First, the ''Bandit'' model assumes that people are different, that experience reveals their characteristics, and that consequently an occupational switch can result. Second, in our ''Stepping-Stone'' model, experience raises a worker's productivity on a given task and the acquired skill can in part be transferred to other occupations, and this prompts movement. Safe activities (where mistakes destroy less output) are a natural training ground.