1
WCOB 1033: Data Analysis and
Interpretation Spring 2015 Final Exam
May 7 (6:00- 8:00pm)
Version A
Please read carefully:
• This is a comprehensive final exam. You are to answer the questions on your own.
You may use your book, your bound materials, a calculator, and a pencil. You may
write on the exam.
• You have 2 hours to complete the exam.
• TURN OFF and put away all electronic devices including (but not limited to): phones,
iPods, laptops, radios, PDAs and digital cameras. Any electronic device that is out,
other than your calculator, will be considered a form of cheating.
• You may not share calculators, books or folders with anyone in the class.
• For all questions involving calculations, choose what you feel is the BEST answer (i.e.,
the response that is closest to your calculations).
Follow these instructions to ensure that you receive credit for this exam:
• Print your name on your answer sheet
• Print your student ID number on your answer sheet and fill in the blanks below.
• Turn in a Scantron with your answers, as well as the exam booklet.
• Complete the following:
Name
Student ID
Instructor Name:
With your signature below, you affirm that you have acted consistently with the University
code of academic integrity.
, 2
Use the scenario below to answer the following three questions.
Historically, the average height of females in the freshman class of a certain college has been 162.5. Is
there reason to believe that there has been a change in the average height if a random sample of 50
females in the present freshman class has an average height of 165.2 centimeters, with a standard
deviation of 6.9 centimeters? Assume the level of significance equals 0.05 and that height is normally
distributed.
1. What is the alternative hypothesis associated with the height of
females? a. μ = 162.5
b. ≠ 165.2
c. μ ≠ 162.5*
d. μ > 165.2
2. What is/are the critical value(s) for this hypothesis
test? a. z = 1.96
b. z = -1.645 and 1.645
c. t = -2.01 and 2.01*
d. z = -1.96 and 1.96
3. What is the test statistic for this hypothesis test and should the null hypothesis be rejected?
a. z = 2.76; reject the null hypothesis
b. t = 2.76; fail to reject the null hypothesis
c. z = 2.76; fail to reject the null hypothesis
d. t = 2.76; reject the null hypothesis*
4. A regression analysis between Sales and Advertising resulted in the following
regression equation: y = 80 + 5x. Sales dollars depend on the amount of Advertising
done in this corporation. Which of the following statements is true?
a. as advertising increases by $1,000, sales increase by $5,000*
b. as advertising increases by $1,000, sales increase by $5,080
c. as advertising increases by $5, sales increase by $80
d. as sales increase by $1,000, advertising increases by $5,080
Use the following scenario for the next three questions.
Trader Moe’s is considering opening a Fayetteville location but their development office has learned that
a main competitor, The Whole Market, currently has a store in development here. Trader Moe’s
conducts a survey to see which store shoppers would choose if both were available within a 5 mile
radius. Out of 200 shoppers surveyed, 73 would go to Trader Moe’s.
5. What is the 95% confidence interval for those who would choose Trader
Moe’s? a. .30 to .44*
b. .33 to .41
c. .56 to .70
d. .69 to .67
6. What is the margin of error in the question
above? a. .03
b. .07*
c. .95
d. 1.96
, 3
7. What would happen to the confidence interval if a 99% confidence level were used?
a. The interval would move to the right along the distribution.
b. The interval would move to the left along the distribution.
c. It would be narrower than the 95% confidence interval.
d. It would be wider than the 95% confidence interval.*
8. A law firm is interested in whether their first year associates are billing more than 55 hours per
week. They ensure that their sample is chosen to reflect the population of lawyers in terms of
the different specialties so that specialty areas are represented in proportion to their size in the
population. This is best described as a:
a. simple random sample.
b. stratified random sample.*
c. cluster sample.
d. random assignment.
Use the information below to answer the following four questions.
Fayetteville Development Company (FDC) wants to develop a regression model to predict operating
margin for its new apartments. Information is available for six explanatory variables: number of
apartments within three miles, number of miles to closest competition, office space in surrounding
community, enrollment in nearby university/college, median household income (in $1000s) in the
surrounding community, and distance (in miles) to the downtown core. Summary information appears
below.
WCOB 1033: Data Analysis and
Interpretation Spring 2015 Final Exam
May 7 (6:00- 8:00pm)
Version A
Please read carefully:
• This is a comprehensive final exam. You are to answer the questions on your own.
You may use your book, your bound materials, a calculator, and a pencil. You may
write on the exam.
• You have 2 hours to complete the exam.
• TURN OFF and put away all electronic devices including (but not limited to): phones,
iPods, laptops, radios, PDAs and digital cameras. Any electronic device that is out,
other than your calculator, will be considered a form of cheating.
• You may not share calculators, books or folders with anyone in the class.
• For all questions involving calculations, choose what you feel is the BEST answer (i.e.,
the response that is closest to your calculations).
Follow these instructions to ensure that you receive credit for this exam:
• Print your name on your answer sheet
• Print your student ID number on your answer sheet and fill in the blanks below.
• Turn in a Scantron with your answers, as well as the exam booklet.
• Complete the following:
Name
Student ID
Instructor Name:
With your signature below, you affirm that you have acted consistently with the University
code of academic integrity.
, 2
Use the scenario below to answer the following three questions.
Historically, the average height of females in the freshman class of a certain college has been 162.5. Is
there reason to believe that there has been a change in the average height if a random sample of 50
females in the present freshman class has an average height of 165.2 centimeters, with a standard
deviation of 6.9 centimeters? Assume the level of significance equals 0.05 and that height is normally
distributed.
1. What is the alternative hypothesis associated with the height of
females? a. μ = 162.5
b. ≠ 165.2
c. μ ≠ 162.5*
d. μ > 165.2
2. What is/are the critical value(s) for this hypothesis
test? a. z = 1.96
b. z = -1.645 and 1.645
c. t = -2.01 and 2.01*
d. z = -1.96 and 1.96
3. What is the test statistic for this hypothesis test and should the null hypothesis be rejected?
a. z = 2.76; reject the null hypothesis
b. t = 2.76; fail to reject the null hypothesis
c. z = 2.76; fail to reject the null hypothesis
d. t = 2.76; reject the null hypothesis*
4. A regression analysis between Sales and Advertising resulted in the following
regression equation: y = 80 + 5x. Sales dollars depend on the amount of Advertising
done in this corporation. Which of the following statements is true?
a. as advertising increases by $1,000, sales increase by $5,000*
b. as advertising increases by $1,000, sales increase by $5,080
c. as advertising increases by $5, sales increase by $80
d. as sales increase by $1,000, advertising increases by $5,080
Use the following scenario for the next three questions.
Trader Moe’s is considering opening a Fayetteville location but their development office has learned that
a main competitor, The Whole Market, currently has a store in development here. Trader Moe’s
conducts a survey to see which store shoppers would choose if both were available within a 5 mile
radius. Out of 200 shoppers surveyed, 73 would go to Trader Moe’s.
5. What is the 95% confidence interval for those who would choose Trader
Moe’s? a. .30 to .44*
b. .33 to .41
c. .56 to .70
d. .69 to .67
6. What is the margin of error in the question
above? a. .03
b. .07*
c. .95
d. 1.96
, 3
7. What would happen to the confidence interval if a 99% confidence level were used?
a. The interval would move to the right along the distribution.
b. The interval would move to the left along the distribution.
c. It would be narrower than the 95% confidence interval.
d. It would be wider than the 95% confidence interval.*
8. A law firm is interested in whether their first year associates are billing more than 55 hours per
week. They ensure that their sample is chosen to reflect the population of lawyers in terms of
the different specialties so that specialty areas are represented in proportion to their size in the
population. This is best described as a:
a. simple random sample.
b. stratified random sample.*
c. cluster sample.
d. random assignment.
Use the information below to answer the following four questions.
Fayetteville Development Company (FDC) wants to develop a regression model to predict operating
margin for its new apartments. Information is available for six explanatory variables: number of
apartments within three miles, number of miles to closest competition, office space in surrounding
community, enrollment in nearby university/college, median household income (in $1000s) in the
surrounding community, and distance (in miles) to the downtown core. Summary information appears
below.
