In statistics, we call the correlation coefficient r, and it measures the strength and direction of a linear relationship between two variables on a scatterplot. The value of r is always between +1 and –1. To interpret its value, see which of the following values your correlation r is closest to:
Exactly –1. A perfect downhill (negative) linear relationship
–0.70. A strong downhill (negative) linear relationship
–0.50. A moderate downhill (negative) relationship
–0.30. A weak downhill (negative) linear relationship
0. No linear relationship
+0.30. A weak uphill (positive) linear relationship
0. No linear relationship
+0.30. A weak uphill (positive) linear relationship
+0.50. A moderate uphill (positive) relationship
+0.70. A strong uphill (positive) linear relationship
Exactly +1. A perfect uphill (positive) linear relationship
Looking at the given scatterplot
r = 0.9
It is not 1 is not a perfect uphill linear relationship, it is close to positive 1
Therefore, r= 0.9