Non-sampling error

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In statistics, non-sampling error is a catch-all term for the deviations of estimates from their true values that are not a function of the sample chosen, including various systematic errors and random errors that are not due to sampling. [1] Non-sampling errors are much harder to quantify than sampling errors. [2]

Non-sampling errors in survey estimates can arise from: [3]

An excellent discussion of issues pertaining to non-sampling error can be found in several sources such as Kalton (1983) [4] and Salant and Dillman (1995), [5]

See also

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Coverage error

Coverage error is a type of non-sampling error that occurs when there is not a one-to-one correspondence between the target population and the sampling frame from which a sample is drawn. This can bias estimates calculated using survey data. For example, a researcher may wish to study the opinions of registered voters by calling residences listed in a telephone directory. Undercoverage may occur if not all voters are listed in the phone directory. Overcoverage could occur if some voters have more than one listed phone number. Bias could also occur if some phone numbers listed in the directory do not belong to registered voters. In this example, undercoverage, overcoverage, and bias due to inclusion of unregistered voters in the sampling frame are examples of coverage error.

In survey sampling, total survey error includes all forms of survey error including sampling variability, interviewer effects, frame errors, response bias, and non-response bias. Total survey error is discussed in detail in many sources including Salant and Dillman.

With the application of probability sampling in the 1930s, surveys became a standard tool for empirical research in social sciences, marketing, and official statistics. The methods involved in survey data collection are any of a number of ways in which data can be collected for a statistical survey. These are methods that are used to collect information from a sample of individuals in a systematic way. First there was the change from traditional paper-and-pencil interviewing (PAPI) to computer-assisted interviewing (CAI). Now, face-to-face surveys (CAPI), telephone surveys (CATI), and mail surveys are increasingly replaced by web surveys.

References

  1. Dodge, Y. (2003) The Oxford Dictionary of Statistical Terms, OUP. ISBN   0-19-920613-9
  2. Fritz Scheuren (2005). "What is a Margin of Error?", Chapter 10, in "What is a Survey? Archived 2013-03-12 at the Wayback Machine ", American Statistical Association, Washington, D.C. Accessed 2008-01-08.
  3. 1 2 U.S. Census Bureau. March 2012. Introduction. Quarterly Financial Report for Manufacturing, Mining, Trade, and Selected Service Industries. Fourth Quarter 2011. p. xxi
  4. Kalton, Graham. Introduction to survey sampling. Vol. 35. Sage, 1983.
  5. Salant, Priscilla, and Don A. Dillman. "How to Conduct your own Survey: Leading professional give you proven techniques for getting reliable results." (1995).