Schooling, employer learning, and internal labor market effect: Wage dynamics and human capital investment in the Japanese steel industry, 1930-1960s

Employer learning model predicts the impact of schooling, an observable signal, on wages decreases with accumulation of experience. Workers, however, have incentives to invest in general human capital both at schools and workplaces such that experience and schooling are complements unless the current employer commits to long-term employment. Microanalysis of Japanese steel industry indeed shows that experience before employed by the firm is complementary to schooling and the complementarity effect dominates employer learning effect while wage growth after employed is consistent with learning hypothesis. It suggests that previous evidences of employer learning might contain internal labor market effect.