Question

What is the correlation coefficient with the following data point: (1,6), (3,2), (7,5), (6,2)

Answer 1

-0.2789

Explanation:

The Correlation Coefficient can be calculated with the following formula

`r=(Cov(X,Y))/(Var(X)Var(Y))`

or

`r=(n \sum XY-(\sum(X)\sum(Y))/(√([n\sum X^2-(\sum X)^2][n\sum Y^2-(\sum Y)^2]))`

We can do the auxiliary calculations in excel and replace in the formula

`r=(4*59-(17*19))/(√([4 * 95-(17)^2][4*69-(15)^2]))=-0.2789`