"Indeed, as a basic Roy model would predict, historical evidence suggests that migration from Western Europe to the US was neutrally selected. Passenger lists of emigrants leaving the German region of Hesse-Cassel in the 1850s reveal that mid-skill level artisans were overrepresented in the migrant flow, as opposed to poor laborers or rich farmers (Wegge, 2002). British immigrants in the 1860s and 1870s were also more likely to have been raised by a father in a semi-skilled profession, as opposed to by an unskilled or white collar father; Long and Ferrie (2013b) observe this pattern in Census data matched between the US and the UK. In contrast, migrants to the US from countries in the European periphery (including Ireland, Norway and Italy) appear to have been negatively selected. Irish migrants from the pre-famine and famine periods held lower-paid occupations than men who remained at home and were more likely to report a round-numbered age; such age heaping is often used as a proxy for a lack of numeracy (Mokyr and Ó Gráda, 1982; Cohn, 1995). Norwegian migrants in a linked Census sample were more likely than non-migrants to be raised by fathers who did not own land and who held lower-paid occupations (Abramitzky, Boustan and Eriksson, 2012). Abramitzky, et al. also find a higher return to migration within pairs of brothers than in the population as a whole, suggesting that naïve estimates of the return to migration are biased downward by negative selection for men leaving urban areas. Spitzer and Zimran (2014) compare the stature of Italian migrants entering the US – logged in Ellis Island arrival records – with the stature of Italian males conscripted into the armed forces as a proxy for childhood health conditions. Migrants were negatively selected on the basis of height from the overall Italian population, due entirely to higher migration rates from the poorer southern provinces."