Q. Explain Correlation Coefficient?

Ans.

The strength of a linear correlation is determined by how precisely the y variable shifts as the x variable increases. The two pictures on the right show data with a higher correlation than those on the left.

Data is said to have a perfect correlation if all points lie exactly along a line.

The correlation coefficient, r, is a measure of the strength of the correlation. It is a number between 1 and +1. +1 indicates a perfect positive correlation and 1 indicated a perfect negative correlation. If r is positive, then there is a positive correlation between the two variables. If r is negative, there is a negative correlation between the variables.