Question

A study was conducted on the relationship between speeds of cars and gas mileage. The correlation coefficient was 0.45. Later, the researchers found the speedometers read 5 mph too high. Researchers recomputed the coefficient. The new value will be:__________. a) 0.40 b) 0.50 c) 0.45

Answer 1

c) 0.45

Step-by-step explanation:

The correlation coefficient measures the relationship between two how two variables change, in this case speed and gas mileage. Since the speedometers were wrong by 5 mph in a constant manner, the correlation between how changes in speed affect gas mileage will not be altered. For example, if you were measuring how an increase of 10 mph decreased gas mileage, you are looking at the change in speed and it is the same if you start with 60 mph and then increase speed to 70 mph, or if you start at 55 mph and then increase to 65 mph, the change in speed will be 10 mph for both.