Write out the multiple regression equation using the given data.
Thompson Machine Works purchased several new, highly sophisticated machines. The production department needed some guidance with respect to qualifications essential by an operator. Four variables were listed.
X1 = Length of time employee was a machinist
X2 = Mechanical aptitude test score
X3 = Prior on-the-job rating
X4 = Age
Performance on the machine is designated Y
The following are the results of the regression analysis;
|
Independent
|
|
Variables
|
Coefficient
|
t-stat
|
|
Intercept
|
11.6
|
2.95
|
|
X1
|
0.4
|
1.23
|
|
X2
|
0.286
|
3.71
|
|
X3
|
0.112
|
4.1
|
|
X4
|
0.002
|
1.86
|
a) Write down out the multiple regression equation.
b) How numerous independent variables are there?
c) Assume the sample size was very large (degrees of freedom is equal to 100), would you consider eliminating any of the independent variables?