1.John Smith has developed the following forecasting model:
Y= 36 + 4.3X1
Y = Demand for KIO air conditioners
X1 = the outside temperature (°F)
a.Forecast the demand for K10 when the temperature is 70°F.
b.What is the demand for a temperature of 80°F?
c.What is the demand for a temperature of 90°F?
2.The operations manager of a musical instrument distributor feels that demand for bass drums may be related to the number of television appearances by the popular rock group Green Shades during the preceding month. The manager has collected the data shown in the following table:
|DEMAND FOR BASS DRUMS||GREEN SHADES TV APPEARANCE|
a.Graph these data to see whether a linear equation might describe the relationship between the group’s television shows and bass drum sales.
b.Using the equations presented in this chapter, compute the SST, SSE, and SSR. Find the least squares regression line for these data.
c.What is your estimate for bass drum sales if the Green Shades performed on TV six times last month?
3.Students in a management science class have just received their grades on the first test. The instructor has provided information about the first test grades in some previous classes as well as the final average for the same students. Some of these grades have been sampled and are as follows:
a.Develop a regression model that could be used to predict the final average in the course based on the first test grade.
b.Predict the final average of a student who made an 83 on the first test.
c.Give the values of r and r2 for this model. Interpret the value of r2 in the context of this problem.
4.Bus and subway ridership in Washington D.C..,during the summer months is believed to be heavily tied to the number of tourists visiting the city.During the past 12 years,the following data have been obtained.
a.Plot these data and determine whether a linear model is reasonable.
b.Develop a regression model.
c.What is expected ridership if 10 million tourists visit the city?
d.If there are no tourists at all,explain the predicted ridership.