The issue of immigration, legal and illegal, has political and economic ramifications. An important component of the issue is how well immigrants integrate into the American economy. A University of Florida study attempted to answer this question. Researchers randomly surveyed U.S. born Americans, immigrants who arrived in the United States before 1980, and immigrants who arrived after 1980 in Miami-Dade County, the state of Florida, and the United States. Each respondent was employed full-time and was asked to report his or her annual earnings. Conduct tests to determine whether differences exist between the three groups in each of the three geographic regions.