Chapter 03.5 Exercise Question 14

Your answer is incorrect.Try again.

If a survey is being conducted on the issue of whether to enact a smoking ban in a public place, how might responses be biased depending on whether or not the interviewer is smoking while asking the questions?

a. Respondents may be less likely to report antismoking opinions.

b. Respondents may be more likely to report antismoking opinions.

Chapter 03.5 Exercise Question 18

Answer the following questions about statistical significance and practical importance:

Explain the distinction between statistical significance and practical importance.

a. Statistical significance tells you the exact value of the parameter and practical importance tells you how big the parameter is.

b. Statistical significance tells you about the strength of evidence against a hypothesized value while practical importance tells you about where we believe the parameter exists.

c. Statistical significance is the opposite of practical importance.

Chapter 03.5 Exercise Question 19

When is the distinction between statistical significance and practical importance more important to consider?

a. when the sample size is small

b. the sample size is irrelevant

c. when the sample size is large

Chapter 03.5 Exercise Question 23

The website www.popvssoda.com invites people to indicate whether they refer to carbonated beverages as "pop" or "soda" or "coke" or something else. As of December 30, 2013, the website had received 350,847 responses from the United States, broken down as follows:

PopSodaCokeOtherTotal131,403149,37754,07215,995350,847

The 95% confidence interval for the population proportion who would answer "soda" is (0.4242, 0.4274).

Based on the results of this calculation, would you say that the sample proportion who answered "soda" is statistically significantly less than 0.50?

a. Yes, significantly greater than 50%.

b. Yes, significantly less than 50%.

Based on how the sample was selected, do you have concerns about generalizing from this sample to any population?

a. We cannot generalize because the sample was not randomly selected

b. We cannot generalize because we do not know if the survey was available in multiple languages

c. We can generalize to all people living the U.S. because the voters were all from the U.S.

d. We can generalize to any population because were collected online

Chapter 03.5 Exercise Question 03

Your answer is incorrect.Try again.

In a November 1992 survey, the Roper Organization asked American adults, "Does it seem possible or does it seem impossible to you that the Nazi extermination of the Jews never happened?" The results were very surprising and widely discussed. Of the 992 adults surveyed, 22% responded that it's possible that this never happened, and 12% responded that they did not know. Therefore, only 66% of the respondents expressed certainty that the Holocaust did happen. What is wrong with the wording of this question that produced such surprising (and it was later shown) erroneous results?

a. People did not know the meaning of the word "extermination"

b. "Impossible that it never happened" contains a double negative