(See attached file for full problem description)
An economist is interested to see how consumption for an economy (in billions) is influenced by gross domestic product (billions) and aggregate price (consumer price index). The Microsoft Excel output of this regression is partially reproduced below.
Multiple R 0.991
R Square 0.982
Adjusted R Square 0.976
Standard error 0.299
df SS MS F SignifF
Regression 2 33.4163 16.7082 186.325 0.0001
Residual 7 0.6277 0.0897
Total 9 34.0440
Coeff StdError t Stat P-Value
Intercept -0.0861 0.5674 -0.152 0.8837
GDP 0.7654 0.0574 13.340 0.0001
Price -0.0006 0.0028 -0.219 0.8330
Referring to the table, when the economist used a simple linear regression model with consumption as the dependent variable and GDP as the independent variable, he obtained an r2 value of 0.971. What additional percentage of the total variation of consumption has been explained by including aggregate prices in the multiple regression?
The correct answer is D. The simple linear regression had explained 97.1% of the total variation in consumption (as ...