The debate about immigration, perhaps today’s hottest domestic issue, usually focuses on the impact of unlettered illegals who sneak across the border for the chance to mow lawns or clean offices. But, according to a body of recent research, low-skill job categories are not the only ones profoundly affected by foreign job seekers. The countless contributions of immigrant researchers to American life--from nuclear power to the TV remote--need no repetition here. But, the data show, the economic forces that depress wages in such immigrant-heavy occupations as off-the-books babysitting and washing restaurant dishes also apply to the incomes of those far higher up the education ladder, such as molecular biologists and computer engineers.

Many people appear to believe that extensive schooling insulates workers from the iron law of supply and demand. A recent paper by Harvard economist George J. Borjas shows, however, that even for doctorate-level researchers, “the supply-demand textbook model is correct after all.” Unlike most economic analysts, Borjas focused not on what foreign-born scientists add to the scientific enterprise or society as a whole but on what their presence costs individual American scientists. For postdocs and other early-career Ph.D.s in a number of fields, unfortunately, the picture he paints isn’t pretty.

Counting the costs

The effect of immigrant workers is two-sided issue, rather like international trade, says economist Paula Stephan of Georgia State University in Atlanta, an expert on the academic labor market. “There are benefits for free trade, but there are also costs,” she explains. “Certain people pay the consequences. When textile factories closed in South Carolina, it may have been better for you and me when we buy cheaper towels, but people in South Carolina got laid off.”

In Science magazine this week ...

Study Finds Foreign High-Tech Workers Earn Less
Yudhijit Bhattacharjee

Many U.S. companies say they hire foreign scientists and engineers because of a shortage of qualified native-born workers. But a new salary study bolsters the claim of some analysts that a strong reason may be to hold down wages.
(Subscription required)

Foreign-born scientists add considerably to the vitality and output of American laboratories, but “an influx into a particular doctoral field at a particular time [has] a significant and adverse effect on the earning of doctorates in the field who graduated at roughly the same time,” Borjas writes. And a significant part of “this adverse wage effect can be attributed to the increased prevalence of low-pay postdoctoral appointments in fields that have softer labor conditions because of large-scale immigration.” An immigrant influx, in other words, increases the likelihood that scientists in the affected field will have to accept postdoc positions.

The article, which examines the effect created by foreign-born scientists who earned their Ph.D.s in the United States, is the first to study “how the foreign student program affects labor market conditions for high-skill workers,” Borjas notes in the paper. “My general impression is that nobody really cared about the impact of foreign students prior to 9/11,” he told NextWave by e-mail. “Our lack of curiosity on some important issues is sometimes astounding.”

Whatever the reason for that previous neglect, Borjas found that “a 10% immigration-induced increase in the supply of doctorates lowers the wage of competing workers by about 3 to 4%,” the paper states. And, adds Stephan, “he’s not just looking at what happens to wages of U.S. citizens.” The pay that the foreign-born scientists themselves receive is also reduced by a large number of fellow immigrants coming into their field. “There’s an immigrant effect on them, too,” she says.

That same hypothetical 10% immigrant influx “increases the probability of being employed in a postdoctoral appointment by 20 to 30%, regardless of whether affected doctorates [sic] are native born or foreign born,” Borjas writes in the paper. And, he continues, “because postdocs earn about 50% less than comparable workers in ‘regular’ jobs, an important wage impact of immigration may be taking place through the ‘crowding’ of workers in immigrant penetrated fields into postdoctoral appointments.”

Borjas’s paper uses detailed data about the numbers of foreign-born students earning U.S. Ph.D.s in a given year but does not provide similarly precise figures for postdocs. Anyone familiar with the current research scene, however, especially in such fields as biology, knows that the flow of foreign-born postdocs vastly exceeds Borjas’s theoretical 10%. “A huge number of them have come. The increase has been quite dramatic recently,” Stephan says. Given this situation, Borjas told NextWave, foreign postdocs “should have a very large effect on the economic forces that determine the earnings of postdocs.”

Counting postdocs

Determining the number of postdocs in the United States, regardless of their nationality, has never been an easy task. Recently, however, Geoff Davis, author of the Sigma Xi postdoc survey conducted between 2003 and 2005, examined some effects on life science postdocs of the doubling of funding for the National Institutes of Health (NIH) that occurred during the last years of the last century and the early years of this one.

Between 1993 and 2004, the number of NIH-supported life science postdocs also nearly doubled, from about 16,000 to about 27,000, according to data compiled by Davis, a Wertheim Fellow at the National Bureau of Economic Research in Cambridge, Massachusetts, and a blogger about science issues. Essentially, “all the growth was in foreign Ph.D.s,” he told NextWave by e-mail. In 1993, just over half of the nation’s life science postdocs were American. Eleven years later, the number of native-born postdocs had risen by about 2000, but foreign postdocs numbered nearly 15,000, not far from the total of all postdocs in 1993. “I believe the story is that graduate enrollments had been more or less flat for awhile before the doubling, so Ph.D. production was pretty flat,” Davis continued. “The doubling happened, and all of a sudden people needed more postdocs. There weren't any more U.S. postdocs to be had, so they were all imported.” Other employment opportunities for new Ph.D.s did not, however, expand commensurately.

What’s more, the effect of that influx of foreign scientists goes beyond depressing incomes all around. “Economic opportunities in high-skill labor markets are among the key determinants of the career decisions made by the native-born student population,” Borjas’s paper states. “Reduced economic opportunities in some fields relative to others … may be an important factor driving native students to enter particular occupations and avoid others.”

For years, numerous studies and commissions have decried the growing propensity of bright Americans to choose careers such as law or business over scientific research. “The wage that could be earned by native postdoctoral workers employed in research labs is much lower than it would have been in the absence of the immigrant influx,” Borjas writes in the paper. But that wage is still an “attractive opportunity” for scientists from countries with living standards much lower than ours. Borjas therefore warns of a “potential ‘vicious cycle’ ” in which immigrant inflows lead to low lab wages, which continue to attract foreign postdocs while seriously discouraging Americans. In short, “the wage effects of large-scale immigration into some doctoral fields are very large and would be expected to be a crucial factor in labor supply decisions” of the native born.

Although Borjas has documented “the costs borne by doctorates in the U.S. labor market,” he emphasizes that no one has analyzed the current system’s benefits, “which could be very large and accrue to particular parts of the population.” Whoever may be benefiting, however, it’s pretty certainly not native-born early-career scientists.

In fact, becoming a scientist generally “is not a good investment” for young Americans, Stephan agrees, “particularly if you think the probability of getting funding so you can be an independent researcher to do the things you want to do is so low.” Indeed, she adds, new programs aimed at reversing these trends, such as NIH’s large new grants to “bridge” the gap between postdoc status and a first faculty post, won’t solve the problem because “the ratio of slots to people is too low, and I’m concerned that it will send very negative signals,” Stephan says. “People will be so disappointed--really, really capable people.”

So what advice does Borjas have for young scientists in fields heavily impacted by immigration? Nothing that would cheer anyone who already has spent a decade or more getting advanced scientific education: “Avoid [those fields] if you want to make money.”

Comments, suggestions? Please send your feedback to our editor.

Beryl Lieff Benderly writes from Washington, D.C.

10.1126/science.caredit.a0700050