A consumer organization wants to develop a regression model to predict mileage (as measured by miles per gallon) based on the horsepower of the car’s engine and the weight of the car (in pounds). Data were collected from a sample of 50 recent car models, and the results are organized and stored in Auto.

Step 1: Copy the data from the word file and paste it into an Excel worksheet.

MPG | Horsepower | Weight |
---|---|---|

43.1 | 48 | 1995 |

19.9 | 110 | 3365 |

19.2 | 105 | 3535 |

17.7 | 165 | 3445 |

18.1 | 139 | 3205 |

20.3 | 103 | 2830 |

21.5 | 115 | 3245 |

16.9 | 155 | 4360 |

15.5 | 142 | 4054 |

18.5 | 150 | 3940 |

27.2 | 71 | 3190 |

41.5 | 76 | 2144 |

46.6 | 65 | 2110 |

23.7 | 100 | 2420 |

27.2 | 84 | 2490 |

39.1 | 58 | 1755 |

28 | 88 | 2605 |

24 | 92 | 2865 |

20.2 | 139 | 3570 |

20.5 | 95 | 3155 |

28 | 90 | 2678 |

34.7 | 63 | 2215 |

36.1 | 66 | 1800 |

35.7 | 80 | 1915 |

20.2 | 85 | 2965 |

23.9 | 90 | 3420 |

29.9 | 65 | 2380 |

30.4 | 67 | 3250 |

36 | 74 | 1980 |

22.6 | 110 | 2800 |

36.4 | 67 | 2950 |

27.5 | 95 | 2560 |

33.7 | 75 | 2210 |

44.6 | 67 | 1850 |

32.9 | 100 | 2615 |

38 | 67 | 1965 |

24.2 | 120 | 2930 |

38.1 | 60 | 1968 |

39.4 | 70 | 2070 |

25.4 | 116 | 2900 |

31.3 | 75 | 2542 |

34.1 | 68 | 1985 |

34 | 88 | 2395 |

31 | 82 | 2720 |

27.4 | 80 | 2670 |

22.3 | 88 | 2890 |

28 | 79 | 2625 |

17.6 | 85 | 3465 |

34.4 | 65 | 3465 |

20.6 | 105 | 3380 |

Step 2: Go to the Data thread and select the option – Data Analysis. From the data analysis dialog box, select the option – Regression.

Step 3: select cells A1 to A51 in the input y range and cells B1 to C51 in the input x range. Select the option of labels and set the confidence level at 95%. Select ‘New Worksheet Ply’ from the Output options. Click on Ok. The regression output will instantly display in a new worksheet.

From the coefficients provided in the regression results, the regression equation is: MPG = 58.16 – 0.11 b^{1}– 0.007 b^{2}

Here, b^{0}= intercept b^{1}= Horsepower of engine b^{2}= Weight

The slope b^{1} shows that with an increase of 1 horsepower in the engine, the mileage of the car decreases by 0.11 miles per gallon and vice versa.

The slope b^{2} shows that with an increase of 1 pound in the cars weight, its mileage will fall by 0.007 miles per gallon and vice versa.

Thus, it can be concluded that both, the horsepower of the car’s engine and the weight of the car are inversely related to its mileage.

The intercept b^{0} has no practical implication as the miles that a car will travel will not have a fixed minimum level beyond which it will depend on the horsepower of the engine and the car weight. This statement does not have any practical basis.

b^{1}= 60 b^2 = 2000 Hence, the miles per gallon (MPG) will be: MPG= 58.16 – (0.11*60) – (0.007*2000) = 37.56 Therefore, the miles per gallon will be 37.56

The confidence interval will be: Y = MPG ± t_{n-2,α/2}*s_{MPG}To calculatet_{n-2,α/2}, select the TINV function in Excel (Formulas -> More Functions -> Statistical -> TINV)

In the TINV dialog box,

Thus, we get the value of t_{α/2}as 2.01 s_{MPG}= 4.176 (from the regression results) Confidence interval = 37.56 ± (2.01*4.176) = (29.16, 45.95)

F. Construct a 95% prediction interval for the miles per gallon for an individual car that has 60 horsepower and weighs 2,000 pounds

The prediction interval will be: Y = MPG ± t_{48,0.05}*√s_{MPG}^{2}+ MSE MSE = 17.44 (from the regression results) Y = 37.56 ± (2.01*√4.176^{2}+17.44) = (25.70, 49.30)

Assignment Writing Help

- Science Assignment Help
- Math Assignment Help
- Chemistry Assignment Help
- Physics Assignment Help
- Biology Assignment Help
- Psychology Assignment Help
- History Assignment Help
- Geography Assignment Help
- English Assignment Help
- Humanities Assignment Help
- Nursing Assignment Help
- Social Science Assignment Help
- Arts and Architecture Help
- Statistics Assignment Help
- Law Assignment Help
- Computational Mathematics Assignment Help

Engineering Assignment Services

- Programming Assignment Help
- Database Help
- Data Structure Assignment Help
- Operating Systems Assignment Help
- Computer Network Assignment Help
- UML Diagram Assignment Help
- IT Assignment Help
- Game Programming Help
- Computer Science Assignment Help
- Information Systems Assignment Help
- Chemical Engineering Assignment Help
- Civil Engineering Assignment Help
- Electrical, Electronics Help
- Mechanical Engineering Assignment Help
- Petroleum Engineering Assignment Help
- Biochemical and Biotechnology Help

Do My Assignment Help

- Accounting Assignment Help
- Finance Assignment Help
- Economics Assignment Help
- Marketing Assignment Help
- Human Resources Assignment Help
- Operations Management Assignment Help
- Strategy and Planning Help
- Project Management Help
- Case Studies Writing Help
- Political science
- Referencing Help
- Assignment Help Websites
- Online Assignment Help
- Do My Assignment
- Do My Homework

Write My Essay Services

- Essay Writing Help
- Business Essay Writing Help
- Assignment Writing Services
- Plagiarism Free Essay Writing
- Essay Editing Service
- Dissertation Writing Services
- Thesis Writing Help
- Custom Writing Help
- Write My Essay
- Write My Paper
- Paper Writing Service
- Academic help
- College Essay Writing
- Cheap Essay Writing