Undercoverage. Oftentimes, an accurate and complete list of the population is unavailable. In such cases, one or more groups will be omitted from the sampling process because they are not listed as part of the population. This type of bias is called undercoverage.

(a) Explain why a sample survey of households will generally suffer from undercoverage.

(b) Provide another example where bias due to undercoverage is likely to occur.

The given statement is:

Oftentimes, an accurate and complete list of the population is unavailable. In such cases, one or more groups will be omitted from the sampling process because they are not listed as part of the population. This type of bias is called undercoverage.

A sample survey of households will generally suffer from undercoverage

This could be because they supply incorrect or disproportionate household structures in their living apartments on purpose.

As a result, the number of households is incomplete.

A telephonic survey is another example where bias due to undercoverage is likely to occur.

There is a risk of undercoverage bias if the researchers select a sample of respondents from the telephonic directory.

This is owing to the fact that not all of the subjects' phone numbers may be listed.

To put it another way, people may use unlisted phone numbers or individuals

does not have access to phones in their homes.

As a result, the phone book does not list all of the people in a given area or country.

As a result, it can be inferred that the telephonic survey has an undercoverage bias.