Question 1

Which of the following best defines a variable in statistics?

Accepted Answer

A variable is a characteristic of the individuals to be measured or observed.

Question 2

In a study of the five movies with the largest worldwide gross receipts, which of the following is an observation for the variable 'studio'?

Accepted Answer

Fox

Question 3

Which of the following is the correct sequence of the five steps in the practice of statistics?

Accepted Answer

Raise a precise question, create a plan, collect data, analyze data, draw a conclusion

Question 4

A researcher surveys 1,024 adults and finds that 67% support a policy. The researcher concludes that 67% of all American adults support the policy. In this context, what is the population?

Accepted Answer

All American adults

Question 5

Which of the following statements about statistics and parameters is correct?

Accepted Answer

A statistic is a numerical summary of a sample.

Question 6

A study uses information from a sample to draw conclusions about the entire population. This practice is called:

Accepted Answer

Inferential statistics

Question 7

In a study, 24 Labrador Retrievers are fed a restricted diet and 24 are fed a normal diet. The study concludes that a typical Labrador Retriever on a restricted diet lives longer. This conclusion is an example of:

Accepted Answer

Inferential statistics

Question 8

Which of the following best describes a simple random sample?

Accepted Answer

A sample where every sample of size $$n$$ has the same chance of being chosen.

Question 9

If a sample is selected such that an individual can be chosen more than once, this is called:

Accepted Answer

Sampling with replacement

Question 10

A college has 19,456 students, of which 11,244 are female. What is the proportion of female students in the population? Express your answer as a decimal rounded to three decimal places.

Accepted Answer

$$0.578$$

Question 11

A random sample of 1,000 students from a college contains 591 females. What is the sample proportion of females? Express your answer as a decimal rounded to three decimal places.

Accepted Answer

$$0.591$$

Question 12

Using the sample proportion $$0.591 to $$estimate the population proportion $$0.578 is an $$example of:

Accepted Answer

Inferential statistics

Question 13

Sampling error is best described as:

Accepted Answer

Error involved in using a sample to estimate information about a population due to randomness in the sample.

Question 14

Which of the following is NOT a type of bias in sampling?

Accepted Answer

Random bias

Question 15

A survey is conducted only among students in the library. Which type of bias is most likely present?

Accepted Answer

Sampling bias

Question 16

A survey asks, 'Should federal funding for SNAP be decreased so the national budget can be balanced?' Which types of bias are present in this question?

Accepted Answer

Sampling bias and response bias

Question 17

Which of the following is an example of nonsampling error?

Accepted Answer

Recording data incorrectly during the survey.

Question 18

An employee randomly selects employees and finds $$\hat{p} = 0.37$$ for those who have worked at least 10 years, but the true population proportion is $$p = 0.38. $$What type of error is present?

Accepted Answer

Sampling error

Question 19

Which guideline is NOT recommended when constructing survey questions?

Accepted Answer

Include judgmental words.

Question 20

A survey about sick leave asks employees if they have ever called in sick when healthy. The sample proportion is $$0.05$$, but the true population proportion is $$0.28. $$What is the most likely explanation?

Accepted Answer

Nonsampling error due to response bias

Designing Observational Studies and Experiments: Simple Random Sampling and Bias

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