Question

Arianna gathered data about the distance of 20 cities from the equator and the average hours of sunlight per day in December for each city. She found the correlation coefficient between the two values to be -0.91. What type of correlation exists between the hours of sunlight and the distance from the equator in Arianna's data? A. strong negative correlation B. weak negative correlation C. strong positive correlation D. weak positive correlation

Answer 1

Answer-

A. strong negative correlation.

Solution-

Direction of a relationship

1. Positive- If one variable increases, the other tends to also increase. If one decreases, the other tends to also. It is represented by positive numbers(i.e 0 to 1).
2. Negative- If one variable increases, the other tends to decrease, and vice-versa.  It is represented by negative numbers(i.e 0 to -1)

Strength of a relationship

1. Perfect Relationship- When two variables are linearly related, the correlation coefficient is either 1 or -1. They are said to be perfectly linearly related, either positively or negatively.
2. No relationship- When two variables have no relationship at all, their correlation is 0.

As in this case, correlation coefficient was found to be -0.91, which is negative and close to -1, so it is a strong negative correlation.