1. When constructing a confidence interval, the value of z* is determined by

Choose the correct answer

a. the sample size.

b. the sample mean.

c. the level of confidence.

d. whether you are working with a random sample or a convenience sample.

e. whether your goal is to estimate an unknown parameter or test a claim about a parameter.

2. A fraternity has sold 1000 raffle tickets in order to raise money for a charity. The prize is a $100 gift card to the campus bookstore. Alex says that the probability that he has the winning ticket is 1. This means Alex must have purchased ____________ raffle ticket(s).

Choose the correct answer

a. 1

b. 10

c. 100

d. 500

e. 1000

3. A 95% confidence interval for the proportion of college students who have texted during class was found to be from 0.75 to 0.95. Which of the following must be the 90% confidence interval from the same sample of data?

Choose the correct answer

a. 0.05 to 0.25

b. 0.777 to 0.9

c. 0.731 to 0.969

d. 0.766 to 0.934

4. A claim is made that 25% of American college students go to a beach for spring break. You believe this claim is incorrect. You would like to test the null hypothesis that p = 0.25 versus the alternative hypothesis that p 0.25. You gather data from a random sample of 100 college students and obtain a test statistic of 3.3. If we assume the significance (or alpha) level is 0.01, what should your decision be?

Choose the correct answer

a. Reject the null hypothesis

b. Fail to reject the null hypothesis

c. Reject the alternative hypothesis

d. Fail to reject the alternative hypothesis

e. We cannot reach a conclusion without knowing the sample proportion.

5. A basketball player keeps track of how many free throws he makes out of 5 attempts. The following probability model describes how likely certain outcomes are. The probability the player will make at least 3 free throws is ________

https://osu.instructure.com/assessment_questions/7292481/files/21607257/download?verifier=60VxBQxj1BnpQiMgDeH6DAXJdnGfTFxzqYNpQgli

Choose the correct answer

a. 0.36.

b. 0.54.

c. 0.64.

d. 0.82

e. 0.18.

6. Which one of the following statements is true?

Choose the correct answer

a. The slope in a regression equation tells us what we predict y to be if x is equal to 0.

b. The correlation coefficient is not resistant outliers.

c. In the context of correlation and regression, as long as the correlation is strong, it's okay to infer that the explanatory variable causes the response variable.

d. If r-squared (or r²) is positive, this means the correlation coefficient (or r) must also be positive.

e. We should use the correlation coefficient and the regression equation only when the relationship between variables is non-linear.

7. Imagine that exactly 40% of adults in the United States regularly listen to podcasts. If we take many random samples of size n = 425 adults from this population, we know the sample proportion who regularly listen to podcasts will vary from sample to sample. We know the sampling distribution in this case would be Normal in shape and would have a standard deviation equal to what value?

Choose the correct answer

a. 0.0485

b. 0.0238

c. 0.4250

d. 0.0006

e. 0.4000

8. Which one of the following statements is false?

Choose the correct answer

a. The standard deviation of the sampling distribution for a proportion will get smaller as the sample size gets bigger.

b. A probability can never be negative.

c. If a person tosses a fair coin 10 times and the first 9 tosses land on "heads," there is a 50% chance the 10th toss will also land on "heads."

d. If a person tosses a fair coin 10 times and the coin lands "tails" all 10 times, the chance it will land "heads" on the 11th toss will be greater than 50%.

9. If a researcher obtained a P-value of 0.01 for a hypothesis test that has a significance level of 0.05, what conclusion should the researcher make?

Choose the correct answer

a. The null hypothesis should not be rejected.

b. The alternative hypothesis should not be rejected.

c. The null hypothesis should be rejected.

d. The alternative hypothesis should be rejected.

e. The null hypothesis must be false.

10. The correlation between temperature and sales is r = 0.67. This means that __________ of the variability in sales can be explained by the regression equation.

Choose the correct answer

a. 6.7%

b. 44.9%

c. 55.1%

d. 67%

e. 81.9%

11. In hypothesis testing, ______________

Choose the correct answer

a. a test statistic is used to measure the difference between the observed sample data and what is expected under the assumption that the null hypothesis is true.

b. if the p-value is 0.99, we should conclude that the null hypothesis is true.

c. if the p-value is 0.01, we should conclude there is a 1% chance the null hypothesis is false.

d. neither the test statistic nor the p-value can ever be negative.

e. results that are statistically significant will always be practically important (or practically significant).