You will want to use software to find the regression equation, either a TI calculator or Statdisk or other software you have found useful.
The sales of a company (in million dollars) for each year are shown in the table below.
|
X (Year)
|
2005
|
2006
|
2007
|
2008
|
2009
|
|
Y (Sales)
|
12
|
19
|
29
|
37
|
45
|
a. Find the least square regression line. How did you handle year? Does your equation appear different than your classmates, if so, why do you think that may have occurred?
b. Use the least squares regression line as a model to estimate the sales of the company in 2012. This is one of the important uses of a regression equation, prediction of values that are not observed.