We construct a multi-layer model of skills, occupations, and sectors. Technological progress among middle-skill occupations raises the employment shares and relative wages of lower- and higher-skill occupations (horizontal polarization), and those of managers over workers (vertical...

We study how various types of machines, namely, information and communication technologies, software, and especially industrial robots, affect the demand for workers of different education, age, and gender. We do so by exploiting differences in the composition of workers across countries,...