In: Statistics and Probability
Corvette, Ferrari, and Jaguar produced a variety of classic cars that continue to increase in value. The data showing the rarity rating (1–20) and the high price ($1000s) for 15 classic cars is contained in the Excel Online file below. Construct a spreadsheet to answer the following questions.
Develop an estimated multiple regression equation
with rarity rating and as the two independent
variables
Price = (___) + (___) Rating + (___) Rating^2 (to whole
numbers)
What is the value of the coefficient of determination? Note: report R^2 between 0 and 1.
(___) (to 3 decimals)
What is the value of the F test statistic?
(___) (to 2 decimals)
What is the p-value?
(to 4 decimals)
Consider the nonlinear relationship shown by equation E(y) = β0β^x1 . Use logarithms to develop an estimated regression equation for this model.
Log(price) = (___) + (___) log(rating) (to 3 decimals)
What is the value of the coefficient of determination? Note: report R^2 between 0 and 1.
(___) (to 3 decimals)
What is the value of the F test statistic?
(___) (to 2 decimals)
What is the p-value?
(___) (to 4 decimals)
Year | Make | Model | Rating | Price ($1000) |
1984 | Chevrolet | Corvette | 18 | 1600.0 |
1956 | Chevrolet | Corvette 265/225-hp | 19 | 4100.0 |
1963 | Chevrolet | Corvette coupe (340-bhp 4-speed) | 18 | 1100.0 |
1978 | Chevrolet | Corvette coupe Silver Anniversary | 19 | 1350.0 |
1960-1963 | Ferrari | 250 GTE 2+2 | 16 | 340.0 |
1962-1964 | Ferrari | 250 GTL Lusso | 19 | 2550.0 |
1962 | Ferrari | 250 GTO | 18 | 350.0 |
1967-1968 | Ferrari | 275 GTB/4 NART Spyder | 17 | 440.0 |
1968-1973 | Ferrari | 365 GTB/4 Daytona | 17 | 150.0 |
1962-1967 | Jaguar | E-type OTS | 15 | 80.0 |
1969-1971 | Jaguar | E-type Series II OTS | 14 | 58.0 |
1971-1974 | Jaguar | E-type Series III OTS | 16 | 125.0 |
1951-1954 | Jaguar | XK 120 roadster (steel) | 17 | 370.0 |
1950-1953 | Jaguar | XK C-type | 16 | 280.0 |
1956-1957 | Jaguar | XKSS | 13 | 67.0 |
Solution
we will solve it by using excel and the steps are
Enter the Data into excel
Click on Data tab
Click on Data Analysis
Select Regression
Select input Y Range as Range of dependent variable as Price
Select Input X Range as Range of independent variable as Rating and Rating^2
click on labels if your selecting data with labels
click on ok.
So this is the output of Regression in Excel.
SUMMARY OUTPUT | ||||||
Regression Statistics | ||||||
Multiple R | 0.8359 | |||||
R Square | 0.6987 | |||||
Adjusted R Square | 0.6485 | |||||
Standard Error | 679.8158 | |||||
Observations | 15.0000 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 2.0000 | 12861143.0501 | 6430571.5251 | 13.9145 | 0.0007 | |
Residual | 12.0000 | 5545794.9499 | 462149.5792 | |||
Total | 14.0000 | 18406938.0000 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | 34003.4758 | 13891.8899 | 2.4477 | 0.0307 | 3735.6479 | 64271.3036 |
Rating | -4596.0463 | 1717.1828 | -2.6765 | 0.0202 | -8337.4661 | -854.6264 |
Rating^2 | 154.4653 | 52.6075 | 2.9362 | 0.0125 | 39.8433 | 269.0873 |
So from the the above output
a.
Price = 34003 - 4596 *Rating + 154*Rating^2
b.What is the value of the coefficient of determination?
coefficient of determination = 0.699
What is the value of the F test statistic?
13.91
What is the p-value?
0.0007
c.Consider the nonlinear relationship shown by equation E(y) = β0β^x1 . Use logarithms to develop an estimated regression equation for this model.
Now take the log of Rating and log of Price and build the regression equation using excel ( procedure is given at the begining)
The data is given below
Log(Price) | Log(Rating) |
3.2041 | 1.2553 |
3.6128 | 1.2788 |
3.0414 | 1.2553 |
3.1303 | 1.2788 |
2.5315 | 1.2041 |
3.4065 | 1.2788 |
2.5441 | 1.2553 |
2.6435 | 1.2304 |
2.1761 | 1.2304 |
1.9031 | 1.1761 |
1.7634 | 1.1461 |
2.0969 | 1.2041 |
2.5682 | 1.2304 |
2.4472 | 1.2041 |
1.8261 | 1.1139 |
Now build regression equation
SUMMARY OUTPUT | ||||||
Regression Statistics | ||||||
Multiple R | 0.8856 | |||||
R Square | 0.7843 | |||||
Adjusted R Square | 0.7677 | |||||
Standard Error | 0.2813 | |||||
Observations | 15.0000 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 1.0000 | 3.7394 | 3.7394 | 47.2611 | 0.0000 | |
Residual | 13.0000 | 1.0286 | 0.0791 | |||
Total | 14.0000 | 4.7679 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | -10.2899 | 1.8754 | -5.4868 | 0.0001 | -14.3414 | -6.2384 |
Log(Rating) | 10.5356 | 1.5325 | 6.8747 | 0.0000 | 7.2248 | 13.8464 |
Log(price) = -10.290 + 10.536log(Rating)
What is the value of the coefficient of determination? Note: report R^2 between 0 and 1.
0.784
What is the value of the F test statistic?
47.26
What is the p-value?
0.0000