Write a detailed note on the degree of correlation.

When reference has been made about the direction of correlation, negative or positive, a natural curiosity arises to know the degree of correspondence or association of the two variables. The maximum degree of correspondence or relationship goes upto 1 (one) in mathematical terms. It can never be more than one. Correlation of 1 is known as perfect correlation (whether positive and negative). Between the two points of divergent perfect correlation lies 0 (zero) correlation a point of correlation or absence of any correlation between the variables.