were used to estimate bias in the original A.C.E. estimates were used as part of the Revision II estimation. Thus, the bias evaluations did not take account of the following sources of error: response error or coding error in the Revision II determination of P-sample residency or match status or E-sample correct enumeration status, which were based on evaluation samples listed in Table 6.3; response error or coding error in the Revision II determination of P-sample mover status; error in the approach used to estimate the contribution to correct enumerations from E-sample cases with duplicate links; error in demographic analysis sex ratios; or error in the model used to estimate correlation bias from these sex ratios (see U.S. Census Bureau, 2003c:68).

The evaluation to construct 95 percent confidence intervals around the Revision II estimates found a possible bias for some population groups (see Mulry and ZuWallack, 2002). In particular, it appears that the Revision II population estimates for non-Hispanic black owners and renters might be too low (U.S. Census Bureau, 2003c:45). The results of the Census and Administrative Records Duplication Study largely account for this result (see Section 6-B.1).

Looking simply at variance from sampling, imputation, and other sources, the Revision II estimates exhibited only slightly larger standard errors than the original A.C.E. estimates, and, in most cases, the Revision II standard errors were lower than the corresponding standard errors for the 1990 PES estimates (see Table 6.7). This result obtained even though many of the data sources used in the Revision II estimation were subsamples of the original A.C.E. The explanation is that the Revision II estimation used data from the full A.C.E. to estimate some components (e.g., E-sample duplications of census enumerations outside the A.C.E. search area), while, for other components (e.g., corrections for measurement error), the estimation used evaluation subsamples to develop correction factors to apply to the full A.C.E. samples. This strategy produced a complex DSE formula with multiple components for each of the elements in the basic formula (see Kostanich, 2003b:15), but it enabled the Revision II estimation to make use of all the available data and not just small evaluation samples as was done for the October 2001 preliminary revised estimates.

A caveat is in order, however. The various E-sample and P-sample correction factors that were developed from subsamples



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