Imagine that you are head of personnel at Huge Corp. The CEO keeps getting other
ID: 3251952 • Letter: I
Question
Imagine that you are head of personnel at Huge Corp. The CEO keeps getting other people’s mail by mistake, so she asks you to conduct a study of mailroom productivity. You take random sample of 27 mailroom employees and gather data on the following variables:
Productivity (PROD=letters correctly sorted per minute),
Experience (EXP=months of experience in the Huge Corp. mailroom), and
Aptitude test score (SCORE=aptitude test score for employees of the Huge Corp.)
You generate the following regression equation:
PROD= 2.0 + 0.5EXP + 0.2SCORE
(4 points) Interpret the slope(s) of the regression equation in this context.
(2 points) Ernest has just been hired, and has an aptitude score of 80. What level of productivity would you expect from Ernest?
(1 points) What is the best interpretation of the intercept term in the regression equation?
a. This is the predicted gain in average productivity for each additional month of experience.
b. This is the predicted gain in average productivity for each additional point of aptitude score.
c. This is predicted average productivity for all new hires.
d. This is the predicted average productivity for new hires with an aptitude score of 0.
(3 points) Jack has 3 months more experience than Jill, but Jill’s aptitude score is 20 points higher than Jack’s. Who is expected to be more productive? Please give a name of the person who is more productive and interpret (show your work!).
Explanation / Answer
We are given,
PROD= 2.0 + 0.5EXP + 0.2SCORE
Question 1)
Slope for EXP:
We can conclude that if there is one unit increment for the variable Experience keeping the variable Aptitude test score as fixed, there will be 0.5 unit increment for the variable Productivity.
Slope for SCORE:
We can conclude that if there is one unit increment for the variable Aptitude test score keeping the variable Experience as fixed, there will be 0.2 unit increment for the variable Productivity.
Question 2)
PROD= 2.0 + 0.5EXP + 0.2SCORE
Answer: 18
Question 3)
d. This is the predicted average productivity for new hires with an aptitude score of 0.
Question 4)
For 3 months there will be increment of (0.5*3) 1.5 unit but for 20 points score the increment will be (0.2*20) 4 unit.
Jill productivity will be more here as 4is greater than 1.5.