Immigrant study produces startling results

U.S. Census Bureau data suggest immigrants are more dispersed and more entwined with U.S.-born people than previously thought.

Geographers Mark Ellis of the University of Washington and Richard Wright of Dartmouth College measured immigrants by the households in which they live, rather than individually on the traditional basis of census tract, neighborhood, metropolitan area or state.

Using 1997-2001 data, Ellis and Wright found there are about 17 million third-generation or more Americans living in households with immigrants or children of immigrants.

They classified immigrants and their descendents by generations into seven different household types to alter the focus from individuals to relationships between individuals.

The scientists defined "foreign-stock households" as those containing at least one foreign-born person or someone who had at least one parent who was foreign-born. Their seven types of households consist of various combinations, such as immigrant-only households and immigrant-second-generation households.

They found 22 percent of the U.S. population is of foreign-stock, but more than 28 percent -- about 76.5 million people -- live in foreign-stock households.

The research appears in the current online edition of the Proceedings of the National Academy of Sciences.