(This question uses information from the article at: www.wired.com/2012/08/fuel-economy-vs-mass/.)

It was of interest to predict the fuel efficiency of petrol powered motor vehicles using their mass. Data was collected on the fuel efficiencies and mass of petrol powered motor vehicles from Wikipedia as follows:

Mass the mass of the vehicle (in kilograms).

CityMPG the fuel efficiency (measured in miles per gallon) when driving on city roads.

The masses of the vehicles ranged between 1000 and 2600 kilograms. A simple linear regression model was fitted to the data and found to satisfy the model assumptions.

The equation of the model was: Predicted CityMPG = 32.788 - 0.0085 Mass

The following output was obtained from the SPSS data editor:

Mass MPG LMCI 1 UMCI 1 LICI 1 UICI 1 2500 10.3947 12.4957 6.2653 16.6252 2510 10.2987 12.4210 6.1778 16.5420 2520 10.2026 12.3464 6.0902 16.4588 2530 10.1065 12.2717 6.0026 16.3757 2540 10.0104 12.1971 5.9150 16.2925