help solve (please show excel formula for part b)
Sol:
in excel install analysis tool pak and then go to
Data>Data analysis>regression
You will get
select Y as
Total project cost
x as billed consulting hours
You will get
SUMMARY OUTPUT | ||||||
Regression Statistics | ||||||
Multiple R | 0.910659 | |||||
R Square | 0.829299 | |||||
Adjusted R Square | 0.819816 | |||||
Standard Error | 324017.6 | |||||
Observations | 20 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 1 | 9.18E+12 | 9.18E+12 | 87.44761 | 2.48E-08 | |
Residual | 18 | 1.89E+12 | 1.05E+11 | |||
Total | 19 | 1.11E+13 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | 742989.2 | 420621.2 | 1.766409 | 0.094281 | -140703 | 1626682 |
Billed consulting hours | 1030.049 | 110.1499 | 9.351343 | 2.48E-08 | 798.6328 | 1261.465 |
From above ouptut
Regression eq is
y=742989+1030*x
which is the answer marked
The 95% confidence interval is
Lower 95% | Upper 95% |
798.6328 | 1261.465 |
ANSWER:
the 95% confidence interval is 798.63 ,1261.47
An engineering firm is interested in investigating whether the variability in the cost of small p...