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### Question 10.

Identify the sampling techniques used and discuss potential sources of bias (if any). Explain.

In 1985, researchers used random digit dialog to call 1300 people and ask what obstacles kept them from buying insurance.

What type of sampling was used?

1. Simple random sampling was used, since each number had an equal chance of being dialed, so all samples of 1300 phones numbers had an equal chance being selected.
2. Convenience sampling was used, since the 1300 phone numbers that were to reach were selected.
3. Cluster sampling was used, since the phone numbers were divided into groups, several groups were selected, and each numbers in those numbers was called.
4. Systematic sampling was used, since phone numbers were selected from a list using a fixed interval between phone numbers.

AnswerOption 1. Simple random sampling was used, since each number had an equal chance of being dialed, so all samples of 1300 phones numbers had an equal chance being selected.