In a 2017 study, economists James Heckman and Rasmus Landersøn compared American and Danish social mobility and found that social mobility is not as high as figures might suggest in the Nordic countries, although they did find that Denmark ranks higher in income mobility. When looking exclusively at wages (before taxes and transfers), Danish and American social mobility are very similar. It is only after taxes and transfers are taken into account that Danish social mobility improves, indicating that Danish economic redistribution policies are the key drivers of greater mobility. Additionally, Denmark's greater investment in public education did not improve educational mobility significantly, meaning children of non-college educated parents are still unlikely to receive college education, although this public investment did result in improved cognitive skills amongst poor Danish children compared to their American peers. There was evidence that generous welfare policies could discourage the pursuit of higher-level education due to decreasing the economic benefits that college education level jobs offer and increasing welfare for workers of a lower education level.