Question 1

Which of the following best describes a population parameter?

Accepted Answer

A numerical summary calculated from the entire population.

Question 2

A researcher wants to estimate the average commute time for all employees at a large company. She randomly selects 100 employees and records their commute times. What is the sample in this scenario?

Accepted Answer

The 100 employees selected and their commute times.

Question 3

Which of the following is a key advantage of randomizing when selecting a sample?

Accepted Answer

It ensures that every possible sample has an equal chance of being selected.

Question 4

A survey is sent to all customers of a company, but only those who feel strongly about the company respond. What type of bias is most likely present?

Accepted Answer

Voluntary response bias

Question 5

Which sampling method involves dividing the population into homogeneous groups and then randomly sampling within each group?

Accepted Answer

Stratified sampling

Question 6

Suppose you want to survey opinions about a new city park. You stand at the park entrance and ask the first 50 people who walk by. What is the main problem with this sampling method?

Accepted Answer

It is likely to suffer from convenience sampling bias.

Question 7

Which of the following best describes sampling variability?

Accepted Answer

The natural differences in results between different random samples.

Question 8

A company wants to know the proportion of its employees who prefer remote work. They randomly select every 5th employee from an alphabetical list, starting from a randomly chosen employee. What sampling method is this?

Accepted Answer

Systematic sampling

Question 9

Why is the size of the sample more important than the fraction of the population sampled?

Accepted Answer

Because the sample size determines the precision of the statistics, regardless of the population size (unless the sample is more than 10% of the population).

Question 10

Which of the following is an example of undercoverage?

Accepted Answer

Surveying only people who are at home during the day about their TV watching habits.

Question 11

A business magazine mails a survey to all Fortune 500 HR directors and receives responses from only 23%. Which bias is most likely present?

Accepted Answer

Nonresponse bias

Question 12

Which of the following is the best way to reduce measurement error in a survey?

Accepted Answer

Pilot test the survey with a small sample.

Question 13

A survey asks, 'Should companies that pollute the environment be compelled to pay the costs of cleanup?' What is the main issue with this question?

Accepted Answer

It is biased due to the wording 'pollute'.

Question 14

Which of the following is NOT a recommended step for ensuring a valid survey?

Accepted Answer

Ask unnecessary questions to gather more data.

Question 15

A researcher divides a city into neighborhoods and randomly selects several neighborhoods. She then surveys every household in those selected neighborhoods. What sampling method is this?

Accepted Answer

Cluster sampling

Question 16

Which of the following is a statistic?

Accepted Answer

The proportion of a sample of 200 students who own a car.

Question 17

A survey is conducted by calling every business listed on a single randomly selected page of the Yellow Pages. What is the main issue with this sampling method?

Accepted Answer

It is likely to include only certain types of businesses, leading to undercoverage.

Question 18

Which of the following best describes a census?

Accepted Answer

A survey that includes the entire population.

Question 19

What is the main benefit of stratified sampling compared to simple random sampling?

Accepted Answer

It reduces sampling variability by ensuring representation from each subgroup.

Question 20

Which of the following is an example of response bias?

Accepted Answer

Respondents give answers they think the interviewer wants to hear.

Surveys and Sampling: Foundations of Statistical Inference

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