Questions 1-5 are based on the following scenario.

A researcher is interested in the average SAT reading section score for all the UCM students. He collects a random sample of 28 students, and the data are as follows. Based on the following data, form a 95% confidence interval for using Student's t-distribution.

58, 48, 48, 41, 34, 43, 38, 53, 41, 60, 55, 44, 43, 49 47, 33, 47, 40, 46, 53, 40, 45, 39, 47, 50, 53, 46, 53

The sample standard deviation is s = 6.73.

1. We cannot use the formula [XZn,X+Zn]in this case, because the population standard deviation is unknown.

Group of answer choices

True

False

2. The standard error of X is _________.

Take your answer to two decimals.

3. For this problem, the degrees of freedom df=_________.

4. Next we find the proper critical t-value for the confidence interval. The t-value is ________. (keep three decimal places)

5. The 95% confidence interval is calculated to be [43.60, ____________]

Take your answer to two decimals.

Questions 6-7 are based on the following scenario.

A researcher is interested in the average height of all the current NBA basketball players, and she randomly draws a sample of 16 players. In this sample, the average height is 78 inches and the sample standard deviation is 3.5. Construct an 80% confidence interval for the population mean height (in inches).

6. The critical value (ie, the t-value) we should use in this confidence interval is _________ (keep three decimal places)

7. The confidence interval is calculated to be [ _________, 79.17]

Take your answer to two decimals.

8. A researcher tries to demonstrate that if parents spend more quality time with their children, children's academic performance will improve. In this case, thenull hypothesisshould be: Children's academic performance will ____________ after parents spend more quality time with their children.

Group of answer choices

A) increase

B) decrease

C) not change

D) decrease or remain the same

9. In hypothesis testing, a researcher willneverbe able to ___________

Group of answer choices

A) accept the null hypothesis

B) reject the null hypothesis

C) fail to reject the null hypothesis

D) retain the null hypothesis

10. In hypothesis testing, a researcher cannever _______________

Group of answer choices

A) retain the null hypothesis

B) make decisions about the null hypothesis

C) prove that his or her argument is correct with 100% certainty

D) know the probability of obtaining the data at hand if the null hypothesis were true

11. Which of the following isNOTa step in hypothesis testing?

Group of answer choices

A) state the hypotheses

B) evaluate the plan

C) make a decision about the hypotheses

D) compute the probability of obtaining the particular data at hand

12. The first step for hypothesis testing requires that the researcher to _____________

Group of answer choices

A) state the hypotheses

B) decide whether there is enough evidence against an argument

C) compute a probability

D) collect data