Deck 21: Paired Samples and Blocks

Question 1

Answer 1

C

Question 2

Which of the following is not an assumption and/or condition for the paired t-test?

A)Nearly Normal Condition
B)Independent Groups Assumption
C)Paired Data Assumption
D)Randomization Condition
E)All of the above

Answer 2

B

Question 3

An army depot that overhauls ground mobile radar systems is interested in improving its processes.One problem involves troubleshooting a particular component that has a high
Failure rate after it has been repaired and reinstalled in the system.The shop floor supervisor
Believes that having standard work procedures in place will reduce the time required for
Troubleshooting this component.Time (in minutes) required troubleshooting this component
Without and with the standard work procedure is recorded for a sample of 19 employees.The
Standard error of the mean difference is

A)25.105
B)2.307
C)0.529
D)4.3589
E)None of the above.

Answer 3

C

Question 4

A mid-sized company has decided to implement an enterprise resource planning (ERP) system, and management suspects that many of its employees are concerned about the
Planned implementation.Managers are considering holding informational workshops to help
Decrease anxiety levels among employees.They randomly select 16 employees to participate
In a pilot workshop.These employees were given a questionnaire to measure anxiety levels
About ERP before and after participating in the workshop.At the 90% confidence level, what
Is the margin of error for the mean difference in anxiety levels pre- and post-workshop?

Question 5

Question 6

Question 7

An army depot that overhauls ground mobile radar systems is interested in improving its processes.One problem involves troubleshooting a particular component that has a high
Failure rate after it has been repaired and reinstalled in the system.The shop floor supervisor
Believes that having standard work procedures in place will reduce the time required for
Troubleshooting this component.Time (in minutes) required troubleshooting this component
Without and with the standard work procedure is recorded for a sample of 19 employees.In
Order to determine if having a standard work procedure in place reduces troubleshooting
Time, they should use

A)a test of two proportions.
B)a two-tailed test of two independent means.
C)a one-tailed test of two independent means.
D)a two-tailed paired t-test.
E)a one-tailed paired t-test.

Question 8

Using the sample paired data below, construct a 90% confidence interval for the population mean of all differences x-y

Question 9

Ten different families are tested for the number of gallons of water a day they use before and after viewing a conservation video.Construct a 90% confidence interval for the mean of the
Differences.

A)(1.8, 7.8)
B)(2.5, 7.1)
C)(3.8, 5.8)
D)(1.5, 8.1)
E)(2.1, 7.5)

Question 10

Question 11

An agricultural company wanted to know if a new insecticide would increase corn yields. Eight test plots showed an average increase of 3.125 bushels per acre.The standard deviation
Of the increases was 2.911 bushels per acre.Determine a 90% confidence interval for the
Mean increase in yield.

A)(2.435, 3.815)
B)(1.175, 5.075)
C)(2.435, 5.075)
D)(1.175, 3.815)
E)(-5.075, -3.815)

Question 12

Question 13

Before being released to market, a drug company tests a new allergy medication for potential side effects.A random sample of 160 individuals with allergies was selected for the study.
The new allergy medication was randomly assigned to 80 of them, and another popular
Allergy medication already on the market (Brand C) was assigned to the rest.Out of the 80
Given the new allergy medication, 14 reported drowsiness; 22 of the 80 taking Brand C
Reported drowsiness.The 95% confidence interval for the difference in proportions reporting
Drowsiness is -0.028 to 0.228.Which of the following is correct?

A)We are 95% confident that there is no difference between the proportions of patients reporting drowsiness for the two allergy medications.
B)We are 95% confident that there is a difference between the proportions of patients reporting drowsiness for the two allergy medications.
C)We are 95% confident that the proportion of patients reporting drowsiness is higher for the new allergy medication.
D)We are 95% confident that the proportion of patients reporting drowsiness is lower for the new allergy medication.

Question 14

A mid-sized company has decided to implement an enterprise resource planning (ERP) system, and management suspects that many of its employees are concerned about the
Planned implementation.Managers are considering holding informational workshops to help
Decrease anxiety levels among employees.To determine whether such an approach would be
Effective, they randomly select 16 employees to participate in a pilot workshop.These
Employees were given a questionnaire to measure anxiety levels about ERP before and after
Participating in the workshop.To determine if anxiety levels about ERP decreases as a result
Of the workshop, they should use a

A)one-tailed test of two proportions.
B)two-tailed test of two independent means.
C)one-tailed test of two independent means.
D)two-tailed paired t-test.
E)one-tailed paired t-test.

Question 15