As in most surveys, persons tend to overreport their participation in the electoral process. Estimates provided by the Election Data Services indicate that 75 million persons voted in the November 1994 elections. As in all surveys, the data in this release are subject to sampling variability and other sources of error, such as survey design flaws, respondent classification errors, and data processing mistakes. The Census Bureau has taken steps to minimize errors, and analytical statements have been tested and meet statistical standards. However, because of methodological differences, use caution when comparing these data with data from other sources.
All demographic surveys suffer from undercoverage of the population.
This undercoverage results from missed housing units and missed persons within sample households. Compared to the level of the 1990 Decennial Census, overall CPS undercoverage is about 8 percent. Undercoverage varies with age, sex, and race. For some groups such as 20 to 29 year old Black males, the undercoverage is as high as 34 percent compared to the Census. The population controls that are used in this survey have been adjusted for undercount in the decennial census and partially correct for the bias due to undercoverage.