From the article:
White House policy adviser Stephen Miller at an Aug. 2 press briefing said that research has found a correlation between low-skilled immigration and declining wages for people in the United States.
When challenged by reporters, Miller said Harvard economist George J. Borjas had analyzed the effect of the Mariel boatlift and found that it did "actually did reduce wages for workers who were living there at the time."...
Borjas’ study, however, has been contested by other experts and academics. (Borjas has also published working papers addressing criticism.)
One of the main criticisms is that he focuses on a relatively small sample size, said Michael Clemens, an economist at the Center for Global Development, a think tank studying ways to reduce global poverty and inequality.
Overall, Miller’s use of Borjas’ research as a case for slashing immigration in half is poor, Clemens said, because the Mariel boatlift influx is not an adequate comparison of current immigration flows. Borjas studied a 20 percent increase in a low-skilled labor force that arrived in Miami over a period of a few months. The current rate of legal immigration is 0.3 percent of the U.S. population (about 323 million) per year, Clemens noted.
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