Using a rich dataset of primary school students in the Netherlands, this paper investigates the heterogeneous effects of immigrant concentration in the classroom on the academic achievement of natives. To identify the treatment effect, it takes advantage of some features of the Dutch primary...

The welfare state was created after 1950 with counterproductive mechanisms and this caused high inflation and high unemployment and stagnating growth by 1970, called stagflation. Since 1970 governments redressed the welfare state but did not succeed in finding workable mechanisms. They rather...

(1) The basic problem in OECD countries is the tax void. (2) A tax system with an exemption is more transparant than a system with a tax credit. (3) Exemption should be at the level of the net minimum wage so that such workers can work at net = gross. (4) A tax credit is a sufficient but not a...