Homework SourseThe sales in billions of dollars of Keller Overhead Door Inc
The sales, in billions of dollars, of Keller Overhead Door Inc. for 2009 to 2014 are:
Use the trend equation to calculate the points for 2011 and 2014. (Round your answers to 3 decimal places.)
By how much have sales increased (or decreased) per year on the average during the period? (Input your answer as positive number. Round your answer to 4 decimal places.)
| Year | Sales | Year | Sales | ||
| 2009 | 7.75 | 2012 | 7.74 | ||
| 2010 | 7.23 | 2013 | 7.86 | ||
| 2011 | 8.87 | 2014 | 7.00 | ||
Solution
Sol) The Regression equation is
y=a+bx
where x is year and y is sales
From Excel
a) The fitted Regression equation is
y = 179.58 -0.085 (year)
B) Now when x=2011
y=179.58 -0.085 (2011)
= 8.645
when x=2014
y=179.58 -0.085 (2014)
=8.39
C)
when x=2017
y=179.58 -0.085 (2017)
y=8.135
D) 0.085 sales will decreased per year on the average during the period
| Coefficients | Standard Error | t Stat | |
| Intercept | 179.5812 | 337.5631 | 0.531993 |
| Year | -0.08543 | 0.167817 | -0.50906 |
