Duplication

Duplication refers to the prevalence of an element more than one time on a sampling frame, assuming that the element appears only once in the target population but appears more than once in the sampling frame. As straightforward as this problem and its solution may appear to be, its detection and correction can be complicated, time-consuming, and/or costly.

For example, a sampling frame made up of names of members of a professional organization may list the same person more than once if the professional organization has not cleaned its list well, so that all but one of the variants of the same name are purged—as in trying to narrow down the following names to only one listing: "Joan F. Smithers," "Joan Smathers," "J. F. Smithers," "J. ...