Walter A. Ewing and Benjamin Johnson examined historical long-series data on Mexican immigrant assimilation as measured by educational and economic status. They conclude:
Despite the formidable obstacles confronting Latin American immigrants, Latinos are in fact experiencing a process of socioeconomic advancement across generations. Those born in the United States achieve average levels of education, income and English proficiency far greater than their immigrant parents and grandparents. However, because a large percentage of contemporary Latinos are first-generation immigrants, these advances across generations are often lost in aggregate statistics that analyze the Latino population as if it were an undifferentiated whole. This calls into question the rhetorical excesses of immigration restrictionists who claim that Latinos are unable or unwilling to replicate the upward mobility of their European predecessors. Moreover, this rhetoric does little to constructively address the important social problems confronting native-born Latinos who already have overcome many of the obstacles faced by their parents and grandparents.Read the whole thing here.
Here's another, more detailed study of the same phenomenon by James P. Smith.
The conventional view regarding Hispanic immigrants’ ability to secure a better life for their children and grandchildren has been pessimistic. They have been seen as not sharing in the successful European experience, perhaps due to a reluctance to assimilate into American culture. These fears are unwarranted: 2nd and 3rd-generation Hispanic men have made great strides in closing their economic gaps with native whites. The reason is simple: each successive generation has been able to close the schooling gap with native whites which then has been translated into generational progress in incomes. Each new Latino generation not only has had higher incomes than their forefathers, but their economic status converged toward the white men with whom they competed. The methodological problems that have marred interpretation of immigrants’ generational progress in schooling and earnings would apply equally to health, where it is alleged that the descendants of immigrants lose their initial health advantage.Read it here.
If you stop and think about it for a second it makes sense. There are plenty of immigrants who don't want to assimilate, but those are the ones who are most likely to return to Mexico. Those who stay are most likely to be the ones who want to assimilate and who push their children to achieve.
Hat tip Tyler Cowen