Gianmarco Ottaviano of the University of Bologna and Giovanni Peri of the National Bureau of Economic Research have shown that immigrants and low-skilled American workers fulfill very different roles in the economy. For instance, 54% of tailors in the U.S. are foreign-born, compared with less than 1% of crane operators. A similar discrepancy exists between plaster-stucco masons (44% immigrant) and sewer-pipe cleaners (less than 1% foreign-born). Immigrants come to the United States with different skills, inclinations and ideas; they are not looking to simply copy the behavior of American workers.
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