In: Statistics and Probability
| SALARY | EDUC | EXPER | TIME |
| 39000 | 12 | 0 | 1 |
| 40200 | 10 | 44 | 7 |
| 42900 | 12 | 5 | 30 |
| 43800 | 8 | 6 | 7 |
| 43800 | 8 | 8 | 6 |
| 43800 | 12 | 0 | 7 |
| 43800 | 12 | 0 | 10 |
| 43800 | 12 | 5 | 6 |
| 44400 | 15 | 75 | 2 |
| 45000 | 8 | 52 | 3 |
| 45000 | 12 | 8 | 19 |
| 46200 | 12 | 52 | 3 |
| 48000 | 8 | 70 | 20 |
| 48000 | 12 | 6 | 23 |
| 48000 | 12 | 11 | 12 |
| 48000 | 12 | 11 | 17 |
| 48000 | 12 | 63 | 22 |
| 48000 | 12 | 144 | 24 |
| 48000 | 12 | 163 | 12 |
| 48000 | 12 | 228 | 26 |
| 48000 | 12 | 381 | 1 |
| 48000 | 16 | 214 | 15 |
| 49800 | 8 | 318 | 25 |
| 51000 | 8 | 96 | 33 |
| 51000 | 12 | 36 | 15 |
| 51000 | 12 | 59 | 14 |
| 51000 | 15 | 115 | 1 |
| 51000 | 15 | 165 | 4 |
| 51000 | 16 | 123 | 12 |
| 51600 | 12 | 18 | 12 |
| 52200 | 8 | 102 | 29 |
| 52200 | 12 | 127 | 29 |
| 52800 | 8 | 90 | 11 |
| 52800 | 8 | 190 | 1 |
| 52800 | 12 | 107 | 11 |
| 54000 | 8 | 173 | 34 |
| 54000 | 8 | 228 | 33 |
| 54000 | 12 | 26 | 11 |
| 54000 | 12 | 36 | 33 |
| 54000 | 12 | 38 | 22 |
| 54000 | 12 | 82 | 29 |
| 54000 | 12 | 169 | 27 |
| 54000 | 12 | 244 | 1 |
| 54000 | 15 | 24 | 13 |
| 54000 | 15 | 49 | 27 |
| 54000 | 15 | 51 | 21 |
| 54000 | 15 | 122 | 33 |
| 55200 | 12 | 97 | 17 |
| 55200 | 12 | 196 | 32 |
| 55800 | 12 | 133 | 30 |
| 56400 | 12 | 55 | 9 |
| 57000 | 12 | 90 | 23 |
| 57000 | 12 | 117 | 25 |
| 57000 | 15 | 51 | 17 |
| 57000 | 15 | 61 | 11 |
| 57000 | 15 | 241 | 34 |
| 60000 | 12 | 121 | 30 |
| 60000 | 15 | 79 | 13 |
| 61200 | 12 | 209 | 21 |
| 63000 | 12 | 87 | 33 |
| 63000 | 15 | 231 | 15 |
| 46200 | 12 | 12 | 22 |
| 50400 | 15 | 14 | 3 |
| 51000 | 12 | 180 | 15 |
| 51000 | 12 | 315 | 2 |
| 52200 | 12 | 29 | 14 |
| 54000 | 12 | 7 | 21 |
| 54000 | 12 | 38 | 11 |
| 54000 | 12 | 113 | 3 |
| 54000 | 15 | 18 | 8 |
| 54000 | 15 | 359 | 11 |
| 57000 | 15 | 36 | 5 |
| 60000 | 8 | 320 | 21 |
| 60000 | 12 | 24 | 2 |
| 60000 | 12 | 32 | 17 |
| 60000 | 12 | 49 | 8 |
| 60000 | 12 | 56 | 33 |
| 60000 | 12 | 252 | 11 |
| 60000 | 12 | 272 | 19 |
| 60000 | 15 | 25 | 13 |
| 60000 | 15 | 36 | 32 |
| 60000 | 15 | 56 | 12 |
| 60000 | 15 | 64 | 33 |
| 60000 | 15 | 108 | 16 |
| 60000 | 16 | 46 | 3 |
| 63000 | 15 | 72 | 17 |
| 66000 | 15 | 64 | 16 |
| 66000 | 15 | 84 | 33 |
| 66000 | 15 | 216 | 16 |
| 68400 | 15 | 42 | 7 |
| 69000 | 12 | 175 | 10 |
| 69000 | 15 | 132 | 24 |
| 81000 | 16 | 55 | 33 |
| SUMMARY OUTPUT | ||||||||
| Regression Statistics | ||||||||
| Multiple R | 0.549576953 | |||||||
| R Square | 0.302034828 | |||||||
| Adjusted R Square | 0.278507912 | |||||||
| Standard Error | 6027.28285 | |||||||
| Observations | 93 | |||||||
| ANOVA | ||||||||
| df | SS | MS | F | Significance F | ||||
| Regression | 3 | 1399124701 | 466374900.2 | 12.83784192 | 4.80E-07 | |||
| Residual | 89 | 3233204332 | 36328138.56 | |||||
| Total | 92 | 4632329032 | ||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
| Intercept | 31794.79804 | 3834.248408 | 8.29231564 | 1.09E-12 | 24176.22813 | 39413.36796 | 24176.22813 | 39413.368 |
| X Variable 1 | 1396.093359 | 277.1248641 | 5.037777335 | 2.45E-06 | 845.4521573 | 1946.734561 | 845.4521573 | 1946.73456 |
| X Variable 2 | 14.84048274 | 6.970537846 | 2.129029792 | 0.036013792 | 0.990172517 | 28.69079297 | 0.990172517 | 28.690793 |
| X Variable 3 | 206.290769 | 61.54401075 | 3.351922738 | 0.001179572 | 84.0041306 | 328.5774075 | 84.0041306 | 328.577407 |
3. Fit a multiple regression model that relates the salary to education, work experience, and time spent at the bank so far.
a - State what your model is.
b - Determine whether the independent variables are significant, or not, at a level of significance of 5%.
c - Which independent variable is most significant in explaining salary? Which is least significant?
d - Is your overall model significant? Provide statistical proof by conducting an F-test for overall fit of the regression. State the hypothesis to be tested, the p-value for your F-statistic, and your decision. How much weight of evidence is there in rejecting the null hypothesis?
| SUMMARY OUTPUT | ||||||||
| Regression Statistics | ||||||||
| Multiple R | 0.549576953 | |||||||
| R Square | 0.302034828 | |||||||
| Adjusted R Square | 0.278507912 | |||||||
| Standard Error | 6027.28285 | |||||||
| Observations | 93 | |||||||
| ANOVA | ||||||||
| df | SS | MS | F | Significance F | ||||
| Regression | 3 | 1399124701 | 466374900.2 | 12.83784192 | 4.80329E-07 | |||
| Residual | 89 | 3233204332 | 36328138.56 | |||||
| Total | 92 | 4632329032 | ||||||
| Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
| Intercept | 31794.79804 | 3834.248408 | 8.29231564 | 1.08909E-12 | 24176.22813 | 39413.36796 | 24176.22813 | 39413.36796 |
| EDUC | 1396.093359 | 277.1248641 | 5.037777335 | 2.44893E-06 | 845.4521573 | 1946.734561 | 845.4521573 | 1946.734561 |
| EXPER | 14.84048274 | 6.970537846 | 2.129029792 | 0.036013792 | 0.990172517 | 28.69079297 | 0.990172517 | 28.69079297 |
| TIME | 206.290769 | 61.54401075 | 3.351922738 | 0.001179572 | 84.0041306 | 328.5774075 | 84.0041306 | 328.5774075 |
a)
Multuple regression:
SALARY = 31794.7980+1396.0934*EDUC+14.8405*EXPER+206.2908*TIME
b)
All independent variables are significanct at 5% significance level because all p values < 0.05
c)
Most significant variable is EDUCATION, Its P value is lessthan 0.00001
Least significant variable is EXPERIANCE, Its P value is between 0.01 < P value < 0.05
d)
Hypothesis:
H0: β1 = β2 = β3
Ha: At least one β is different
F stat = 12.8378
P value = 0
P value < 0.05
There is a strong evidence to conclude that Regression is significant at 5% significance level