The 1991 Census Adjustment: Undercount or Bad Data?

Abstract

The question of whether to adjust the 1990 census using a capture-recapture model has been hotly argued in statistical journals and courtrooms. Most of the arguments to date concern methodological issues rather than data quality. Following the Post Enumeration Survey, which was designed to provide the basic data for adjustment, the Census Bureau carried out various evaluation studies to try to determine the accuracy of the adjusted counts as compared to the census counts. This resulted in the P-project reports, which totaled over a thousand pages of evaluation descriptions and tables. Careful scrutiny of these studies together with auxiliary sources of information provided by the Census Bureau is used to examine the issue of whether the data gathered in the Post Enumeration Survey can provide reliable undercount estimates.