Annual Demographic Survey (March Supplement)

How to Estimate Sampling Errors


Since estimates from the Annual Demographic Survey come from a sample, they may differ from figures from a complete census using the same questionnaires, instructions, and interviewers. A sample survey estimate has two possible types of error: sampling and nonsampling. The accuracy of an estimate depends on both types of error, but the full extent of the nonsampling error is unknown. Consequently, one should be particularly careful when interpreting results based on a relatively small number of cases or on small differences between estimates. The standard errors for CPS estimates primarily indicate the magnitude of sampling error. They also partially measure the effect of some nonsampling errors in responses and enumeration, but do not measure systematic biases in the data. (Bias is the average overall possible samples of the differences between the sample estimates and the desired value.)

Several examples of how to estimate sampling errors for the 1994 Annual Demographic Survey are given in the Source and Accuracy Statement.


Annual Demographic Survey (March CPS Supplement) Making Estimates Page

CPS Home Page


Author: Lloyd Hicks-Census/DSMD/???
Contact: (ask.census.gov) CPS Help-Census/DSD/CPSB
Last modified: May 23, 1996
URL: http://www.bls.census.gov/cps/ads/1995/ssamperr.htm