To be a STEM or not to be a STEM: Why do countries differ?

This paper proposes a theoretical analysis and an empirical investigation on simultaneous choices of an enrolment and discipline field, comparing science, technology, engineering, and mathematics (STEM) to non-STEM fields, to enlighten economic variables influencing students. The cross-country analysis of 35 countries in the period 2013-2016 tries to disentangle factors shifting students from one choice to another and why countries differ in directing students toward specific disciplines. The results show that expenditures in R&D convince more students to choose STEM disciplines, whereas population density and the expected years of schooling have a negative impact on the percentage of STEM enrolments. As a whole, it appears that STEM enrolments are chosen for investment motives, whereas non-STEM enrolments are less guided by economic factors and more dependent on a consumption effect.