The degree or the extent of correlation between two variables is described by the value of the correlation coefficients. The degrees of correlation are: Perfect Correlation, Zero Correlation, Limited Degree of Correlation
If there is no relation between two variables, i.e. change in one variable has no effect on the change in the other, then the variable lacks correlation. The value of the correlation coefficient for zero correlation equals zero.
Note: A zero correlation between any two variables does not mean that there is no relationship at all between them. In fact, it should be interpreted that the 2 variables are not linearly related. However, it may be possible that the two variables may be nonlinearly related to each other.
A positive correlation between two variables exists when both of them move in the same direction And the negative correlation between two variables
Correlation is a statistical tool that measures the quantitative relationship between different variables. It studies the degree and intensity of the connection between the two variables. The relationship between two variables is studied with the help of a statistical tool i.e. ‘Correlation’.
Dispersion measures the extent to which the different items tend to disperse away from the central tendency. In other words, while central tendency indicates a representative value, the measures of dispersion indicate the divergence of the values of different items from the central value.