Question

A study was conducted on the relationship between the speed of different cars and their gas mileage. The correlation coefficient was found to be 0.35. Later, it was discovered that there was a defect in the speedometers, and they had all been set 5 miles per hour too fast. The correlation coefficient was computed using the corrected scores. Its new value will be:

A) -0.35

B)

0.40

C)

0.35

D)

0.30

Answer 1

Earlier correlation coefficient =0.35

New correlation coefficient= 0.35

There will not be any change in the correlation coefficient this is because it is the property of the correlation coefficients that it is unitless. It means whatever you do with the data but correlation coefficient will not change and remain the same.

You can take an example. Make a 2 table and fill 5 data in each and then calculate the correlation coefficient now after calculations add any number let us say 5 with second list and then calculate correlation coefficient between the new table and old table. You will see that the value remains the same.

So option C is correct