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Heterogeneous Wage Effects of Apprenticeship Training

Relatively small average wage effects of employer and occupation changes after apprenticeship training mask large differences between occupation groups and apprentices with different schooling backgrounds. Employer and occupation changers in industrial occupations enjoy large wage advantages, whereas apprentices in commerce and trading occupations, as well as in construction and crafts occupations, face wage losses from an occupation change. Differences between the firms that provide the apprenticeship training are found to be small or insignificant. This paper reconciles differences between previous findings by comparing and replicating their empirical estimation strategies. It demonstrates that selectivity in occupations and changes, unobserved heterogeneity between occupations, and sample selection matter.