To estimate support for a school bond measure, a survey firm randomly dials landline telephone numbers in the school district. About 35% of district households no longer have a landline and use only cell phones.
Which type of bias is most likely present?
- A
Voluntary response bias
- Bcheck_circle
Undercoverage bias
- C
Response bias
- D
Nonresponse bias
Explanation
Cell-phone-only households cannot be selected at all, so a portion of the population is systematically excluded from the sampling frame. This is undercoverage bias.