In: Statistics and Probability
MULTIPLE REGRESSION
The date set below was collected from a random sample of 15 households on the following variables: (1) Weekly Income, (2) House Rent, (3) Food Expense, (4) Entertainment Expense, and (5) Weekly Savings.
Sampled Weekly House
Food
Entertain/ Weekly
Individual Income Rent
Expense Expense
Savings
Case 1 $250
85 95
25 20
Case 2 $190
75 90
10 0
Case 3 $420
140 120
40 50
Case 4 $340
120 130
0 40
Case 5 $280
110 100
30 15
Case 6 $310
80 125
25 25
Case 7 $520
150 140
55 80
Case 8 $440
175 155
45 0
Case 9 $360
90 85
20 95
Case 10 $385
105 135
35 30
Case 11 $205
80 105
0 5
Case 12 $265
65 95
15 15
Case 13 $195
50 80
10 20
Case 14 $250
90 100
25 0
Case 15 $480
140 160
45 45
A multiple regression was run with WEEKLY SAVINGS as the DEPENDENT VARIABLE and the rest as the INDEPENDENT VARIABLES.
SAVINGS = b + b INCOME + b RENT + b FOOD + b ENTERT
The resulting computer output is on the next page.
COMPUTER OUTPUT PART I
WEEKLY SAVINGS
REGRESSION FUNCTION & ANOVA FOR SAVINGS
SAVINGS = 23.14156 + 0.591446 INCOME - 0.341793 RENT
- 1.119734 FOOD - 0.907868 ENTERT
R-Squared = 0.917562
Adjusted R-Squared = 0.870454
Standard error of estimate = 10.9635
Number of cases used = 12
Analysis of Variance
p-value
Source SS df MS F Value Sig
Prob
Regression 9364.86 4 2341.21
19.47795 0.000677
Residual 841.39 7 120.198
Total 10206.250 11
COMPUTER OUTPUT PART II
WEEKLY SAVINGS
REGRESSION COEFFICIENTS FOR SAVINGS
Two-Sided p-value
Variable Coefficient Std
Error t Value Sig Prob
Constant 23.14156 18.34071
1.26176 0.247451
INCOME 0.59145 0.07388
8.00526 0.000091
RENT -0.34179 0.19849
-1.72199 0.128743 *
FOOD -1.11973
0.24633 -4.54565 0.002650
ENTERT -0.90787 0.32460
-2.79689 0.026643
* indicates that the variable is marked for leaving
Standard error of estimate = 10.9635
Durbin-Watson statistic = 1.683103
Use the above computer output to respond to the following
questions:
The Model was:
(a) The multiple regression model is:
ANSWER
(b) What is the estimated multiple regression?
ANSWER
(c) What are the estimated values of b , b , b , b ,
and b ?
ANSWERS b = ?
b = ?
b = ?
b = ?
b = ?
(d) What relationship exists between (i) SAVINGS and
INCOME?, SAVINGS and RENT?, SAVINGS and FOOD expense, SAVINGS and
ENTERTAINMENT expense?
ANSWERS
(e) Which of the four independent (explaining) variables are (is) significant in the multiple regression and which ones are (is) not significant and why? (Use α = 0.05 level of significance). Use α = 0.05 level ANSWERS
The statistically significant explaining variables are (Use α = 0.05 level):
Those that are not significant (Use α = 0.05 level):
(f) Are the results in line with Maslow’s hierarchy of
needs? Explain.
Solution:
Part(a): Multiple regression model is,
here, Y is independent variable, is intercept , are slopes and x1,x2,x3 and x4 are independant variable.
Part(b): Estimated multiple regression model is,
Y=23.14156+0.5914 Income -0.3417 Rent -1.1197 Food -0.90787 Expense
Part (c): following are values estimated for intercept and slopes:
alpha (intercept)=23.14156
b1=0.5914
b2=-0.3417
b3=-1.1197
b4=-0.90787
Part(d): Weekly savings has significant linear relationship with variables weekly income, food and entertainment expenses.
Weekly savings has not linear relationship with rent.
Part (e): Weekly income, food and entertainment expenses there independent variables comes out be significant because p-values associated with these variables are less than 0.05 (significance level) therefore, we reject the null hypothesis that slope=0.
Independent variable rent is not significant because its p-value greater than level of significance alpha.