Question 1

When do you reject the null hypothesis?

Question 1 options:

When the p-value is larger than a preconceived alpha

When the p-value is smaller than a preconceived alpha

When the p-value is equal to a preconceived alpha

Question 2

Use the following for the next two questions. The mean age of graduate students at a University is at most 31 years with a standard deviation of two years. A random sample of 15 graduate students is taken. The sample mean is 32 years and the sample standard deviation is three years. The p-value is 0.0264.

State the null and alternative hypotheses.

Question 2 options:

H0: 31 and Ha: < 31

H0: = 31 and Ha: 31

H0: 31 and Ha: > 31

Question 3

Are the data significant at the 1% level?

Question 3 options:

The p-value is 0.0264, so the data are significant at the 1% level.

The p-value is 0.0264, so the data are not significant at the 1% level.

Question 4

What should you do when > p-value?

Question 4 options:

Reject H0.

Fail to reject H0.

Question 5

If you do not reject the null hypothesis, then it must be true. Is this statement correct? Why or why not?

Question 6

Use the following for the next 3 questions.Suppose that a recent article stated that the mean time spent in jail by a first-time convicted burglar is 2.5 years. A study was then done to see if the mean time has increased in the new century. A random sample of 26 first-time convicted burglars in a recent year was picked. The mean length of time in jail from the survey was three years with a standard deviation of 1.8 years. Suppose that it is somehow known that the population standard deviation is 1.5. Conduct a hypothesis test to determine if the mean length of jail time has increased. Assume the distribution of the jail times is approximately normal.

xrepresents the random variable for this test.

Question 6 options:

True

False

Question 7

Is the population standard deviation known and, if so, what is it?

Question 7 options:

No

Yes, 1.2

Yes, 1.5

Question 8

If both and s_xare given, which should be used?

Question 8 options:

s_x

Either one is fine

Question 9

Assume H0: 6 and Ha: > 6. Is this a left-tailed, right-tailed, or two-tailed test?

Question 9 options:

A left-tailed test

A right-tailed test

A two-tailed test

Question 10

A bottle of water is labeled as containing 16 fluid ounces of water. You believe it is less than that. What type of test would you use?

Question 10 options:

A left-tailed test

A right-tailed test

A two-tailed test

Question 11

A bathroom scale claims to be able to identify correctly any weight within a pound. You think that it cannot be that accurate. What type of test would you use?

Question 11 options:

A left-tailed test

A right-tailed test

A two-tailed test

Question 12

Use the following for the next 5 questions. A random survey of 75 death row inmates revealed that the mean length of time on death row is 17.4 years with a standard deviation of 6.3 years. Conduct a hypothesis test to determine if the population mean time on death row could likely be 15 years.

State the null and alternative hypotheses. H0: _________________ Ha: ______________

Question 12 options:

H0: = 15 Ha: > 15

H0: = 15 Ha: 15

H0: p = 15 Ha: p > 15

Question 13

Identify the following:

x,s,andn.

Question 13 options:

x= 17.2,s= 6. 2 andn= 65

x= 17.4,s= 6. 3 andn= 75

x= 17.6,s= 6. 4 andn= 85

Question 14

Which test should be used?

Question 14 options:

t₇₄

t₇₅

z₇₄

z₇₅

Question 15

Find the p-value.

Question 15 options:

0.0007

0.0009

0.0011

0.0015

Question 16

At a preconceived = 0.05, you should do which of the following?

Question 16 options:

Reject the null hypothesis becausep-value < alpha.

Reject the null hypothesis because p-value > alpha.

Accept the null hypothesis becausep-value < alpha.

Accept the null hypothesis becausep-value > alpha.

Question 17

The mean number of sick days an employee takes per year is believed to be about 10. Members of a personnel department do not believe this figure. They randomly survey eight employees. The number of sick days they took for the past year are as follows: 12; 4; 15; 3; 11; 8; 6; 8. Let x = the number of sick days they took for the past year. Assume that the underlying population is normally distributed. Assume = 0.05. Should the personnel team believe that the mean number is 10? Show all work to arrive at your conclusion (provide the null and alternative hypothesis, the p-value, state whether you reject or do not reject the null hypothesis, and the reason for your decision). Clearly state your conclusion.