Study Search Results Your query returned 1 results. Series results are grouped under the most relevant study. You can ungroup series results. Results per page: 25 50 100 Sort by: Study Relevance Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. Variable Relevance (?) Study Title/Investigator 1. Cross-National Equivalent File (CNEF), 1970-2009 (ICPSR 145) Cornell University. Department of Policy Analysis and Management; University of Michigan. Institute for Social Research. Panel Study of Income Dynamics; German Institute for Economic Research (DIW Berlin); et al.