In: Statistics and Probability
Question 2:
Personal wealth tends to increase with age as older individuals have had more opportunities to earn and invest than younger individuals. The following data were obtained from a random sample of eight individuals and records their total wealth (Y) and their current age (X).
Person |
Total wealth (‘000s of dollars) Y |
Age (Years) X |
A |
280 |
36 |
B |
450 |
72 |
C |
250 |
48 |
D |
320 |
51 |
E |
470 |
80 |
F |
250 |
40 |
G |
330 |
55 |
H |
430 |
72 |
A part of the output of a regression analysis of Y against X using Excel is given below:
SUMMARY OUTPUT |
|||||||||||
Regression Statistics |
|||||||||||
Multiple R |
0.954704 |
||||||||||
R Square |
0.91146 |
||||||||||
Adjusted R Square |
0.896703 |
||||||||||
Standard Error |
28.98954 |
||||||||||
Observations |
8 |
||||||||||
ANOVA |
|||||||||||
df |
SS |
MS |
F |
Significance F |
|||||||
Regression |
1 |
51907.64 |
51907.64 |
||||||||
Residual |
6 |
5042.361 |
840.3936 |
||||||||
Total |
7 |
56950 |
|||||||||
Coefficients |
Standard Error |
t Stat |
P-value |
||||||||
Intercept |
45.2159 |
39.8049 |
|||||||||
Age |
5.3265 |
0.6777 |
|||||||||
Step 1. Statement of the hypotheses
Step 2. Standardised test statistic
Step 3. Level of significance
Step 4. Decision Rule
Step 5. Calculation of test statistic
Step 6. Conclusion