Question 1

Which of the following best describes the difference between 'statistics' as a science and 'statistics' as data?

Accepted Answer

Statistics as a science refers to the process of collecting, organizing, and interpreting data, while statistics as data refers to the actual numbers or information that describe something.

Question 2

In a study to determine the average weight of potatoes delivered to a fast food restaurant each week, what is the population?

Accepted Answer

All the potatoes delivered each week for making French fries.

Question 3

A researcher surveys 1,000 adults to estimate the percentage of all adults who support a new policy. The percentage calculated from the survey is called:

Accepted Answer

A sample statistic

Question 4

Which of the following is an example of a population parameter?

Accepted Answer

The actual unemployment rate among all members of the civilian labor force.

Question 5

Suppose a poll finds that 60% of a sample of 2,000 voters support a candidate, with a margin of error of 2%. What is the 95% confidence interval for the population parameter?

Accepted Answer

$$60\% \pm 2\% = [58\%, 62\%]$$

Question 6

Which step in a statistical study involves making inferences about the population based on sample statistics?

Accepted Answer

Step 4

Question 7

Why is it important to choose a representative sample in a statistical study?

Accepted Answer

To ensure that the sample statistics provide accurate estimates of the population parameters.

Question 8

In the Salk polio vaccine experiment, what was the sample?

Accepted Answer

The 400,000 children chosen from the population of all children in the United States.

Question 9

If a survey of 9,680 adults finds that 74% believe media criticism of politicians is worthwhile, with a margin of error of 1.3%, what is the likely range for the true population percentage?

Accepted Answer

$$[72.7\%, 75.3\%]$$

Question 10

Which of the following best describes the purpose of statistics?

Accepted Answer

To help us make good decisions about issues that involve uncertainty.

Question 11

A company wants to estimate the average amount paid to accident victims in cars without side-impact airbags. Which of the following is a population parameter in this context?

Accepted Answer

The average (mean) amount paid to all accident victims in cars without side-impact airbags.

Question 12

Which of the following is NOT a basic step in a statistical study?

Accepted Answer

Ignoring the sample and using only the population.

Question 13

If the margin of error for a poll is reduced, what does this imply about the sample size?

Accepted Answer

The sample size has increased.

Question 14

Which of the following is an example of raw data?

Accepted Answer

The individual responses collected from each person in a survey.

Question 15

Descriptive statistics is primarily concerned with:

Accepted Answer

Describing raw data in the form of graphics and sample statistics.

Question 16

Inferential statistics is primarily concerned with:

Accepted Answer

Estimating population parameters from sample data.

Question 17

A survey finds that 31% of a sample watched the Super Bowl. What is the population parameter of interest?

Accepted Answer

The percentage of all Americans who watched the Super Bowl.

Question 18

Which of the following statements about the margin of error is correct?

Accepted Answer

The margin of error describes the range likely to contain the population parameter with a certain level of confidence.

Question 19

In the context of the unemployment survey, which of the following is a sample statistic?

Accepted Answer

The percentage of people in the 60,000 surveyed households who are actively seeking employment.

Question 20

Why might the margin of error be larger for subgroups (such as Democrats or Republicans) than for the full sample?

Accepted Answer

Because the sample sizes for subgroups are smaller, increasing uncertainty.

Introduction to Statistics: Concepts, Definitions, and the Statistical Study Process

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