What is sampling bias and response bias? Give an example for each.

• A. Sampling bias occurs when the sample is not representative (e.g., phone surveys miss non-phone households).
• B. Response bias occurs when respondents misreport (e.g., social desirability).
• C. Sampling bias occurs when the sample is not representative; Response bias occurs when respondents misreport.
• D. Sampling bias occurs when data are transformed; response bias occurs when data are missing.

Answer: (C)

Sampling bias happens when the group you study isn’t representative of the whole population because of how you choose participants. For example, phone surveys can miss people who don’t have phones or who don’t answer unknown numbers, so the results don’t reflect everyone.

Response bias occurs when participants don’t report their true thoughts or behaviors, often to present themselves in a favorable light. For example, people might say they exercise more than they actually do to seem healthier.

The best choice covers both ideas: sampling bias as a non-representative sample and response bias as misreporting. The other options describe only one bias or mix in unrelated data issues, which aren’t definitions of these biases.