Noah Smith interviews Leah Boustan about her research on various aspects of immigration at his Noahpinion website.

In answer to a question about “the biggest popular misconceptions about immigration in America today,” Boustan responds:

Americans vastly overestimate how many immigrants are in the country today. According to a survey conducted by Stefanie Stantcheva and her co-authors, Americans guess that 36% of the country is born abroad, whereas the real number is 14%. So, this misconception gives rise to fears that we are in an “immigration crisis” or that we have a “flood” of immigrants coming to our shores. In reality, the immigrant share of the population today (14%) only just reached the same level as it was during the Ellis Island period for over 50 years! After this, I would say that the second biggest misconception is that immigrants nowadays are faring more poorly in the economy and are less likely to become American than immigrants 100 years ago.

On the issue of how immigrants do at catching up economically:

We find that Mexican immigrants and their children achieve a substantial amount of integration, both economically and culturally. First, on the economic side, we compare the children of Mexican-born parents who were raised at the 25th percentile of the income distribution — that’s like two parents working full time, both earning in the minimum wage — to the children of US-born parents or parents from other countries of origin. The children of Mexican parents do pretty well! Even though they were raised at the 25th percentile in childhood, they reach the 50th percentile in adulthood on average. Compare that to the children of US-born parents raised at the same point, who only reach the 46th percentile. Of course, children of other immigrant backgrounds do even better, but the children from Mexican households are experiencing a lot of upward mobility. …

[T]he pattern … whereby the kids of poor and working-class immigrants do better than their American counterparts, is true both today and in the past. The children of poor Irish or Italian immigrant parents outperformed the children of poor US-born parents in the early 20th century; the same is true of the children of immigrants today. 

We are able to delve into the reasons for this immigrant advantage in the past in great detail, and we find that the single most important factor is geography. Immigrants tended to settle in dynamic cities that provided opportunities both for themselves and for their kids. So, in the past, this meant avoiding Southern states, which were primarily agricultural and cotton-growing at the time, and – outside of the South – moving to cities more than to rural areas. If you think about it, it makes sense: immigrants have already left home, often in pursuit of economic opportunity, so once they move to the US they are more willing to go where the opportunities are. 

Geography still matters a lot today, but not as much as in the past. Instead, we suspect that educational differences between groups matter today. Think about a Chinese or Indian immigrant who doesn’t earn very much, say working in a restaurant or a hotel or in childcare. In some cases, the immigrant him or herself arrived in the US with an education – even a college degree – but has a hard time finding work in their chosen profession. Despite the fact that these immigrant families do not have many financial resources, they can pass along educational advantages to their children.

On the issue of how immigrants assimilate culturally, Boustan comments:

We are economists, so the first work we did on immigration was focused on economic outcomes like earnings and occupations. But, voters often care more deeply about cultural issues – both in the past and today. So, we realized that we wanted to try to measure ‘fitting in’ or cultural assimilation using as many metrics as we could find. We looked at learning English, of course, but also who immigrants marry, whether immigrants live in an enclave neighborhood or a more integrated area, and – one of our favorite measures – the names that immigrant parents choose for their children. These are all measures that can be gathered for immigrants today and 100 years ago; there are other metrics for today that don’t exist for the past — like ‘do immigrants describe themselves as patriotic’ (answer is: they do).

What we learned is that immigrants take steps to ‘fit in’ just as much today as they did in the past. So, for example, we can look at the names that immigrant parents choose for their kids. Both in the past and today, immigrants choose less American-sounding names for their kids when they first arrive in the US, but they start to converge toward the names that US-born parents pick for their kids as they spend more time in the country. Immigrants never completely close this ‘naming gap’ but they move pretty far in that direction, both then and now.