I formulate and estimate a model of externalities within countries and technological interdependence across countries. I find that external returns to scale to physical capital within countries are 8 percent; that a 10 percent increase of total factor productivity of a country's neighbors raises...

The purpose of the research is to analyze and investigate the interest of primary school pupils in natural science topics within primary school subject fields. Examining the existing curricula, it becomes evident that natural science topics are intertwined in different subject fields. Based on...