Which sampling method uses interviewers with quotas to fill and may lead to non-random samples?

• A. Systematic random sampling
• B. Cluster sampling
• C. Sample survey
• D. Quota sampling

Answer: (D)

In survey sampling, non-probability methods include quota sampling, where interviewers are given quotas to fill and aim to match certain characteristics in the sample. Respondents are selected as they are encountered rather than chosen randomly, so the chance of any individual being included isn’t known. This can lead to bias because the sample depends on who is available and who the interviewer happens to approach.

This method fits the description because it explicitly uses interviewers with quotas and acknowledges the risk of a non-random sample. Systematic random sampling, by contrast, selects every kth person after a random start and aims for randomness; cluster sampling involves randomly selecting entire groups and then surveying within them; and a sample survey is a general term that doesn’t specify the quota-driven approach.