in the simple linear regression equation let b

(iii) Amount of rainfall and yield of crops

Positive correlation: If the two variables deviate in the same direction, i.e., if the increase (or decrease) in one variable results in a corresponding increase (or decrease) in the other variable, correlation is said to be direct or positive. Having made a set of paired observations ( x i,y i) i = 1, …, n, from n, independent sampling units, a measure of the linear relationship between two variables can be obtained by the following quantity called Pearson’s product moment correlation coefficient or simply correlation coefficient.ĭefinition: If the change in one variable affects a change in the other variable, the two variables are said to be correlated and the degree of association ship (or extent of the relationship) is known as correlation.Ī). In such instances, an investigator may be interested in measuring the strength of the relationship. Strong correlation is found to occur between several morphometric features of a tree. For instance, several soil properties like nitrogen content, organic carbon content or pH are correlated and exhibit simultaneous variation. In other words, there is a correlation between the two variables. In many natural systems, changes in one attribute are accompanied by changes in another attribute and that a definite relation exists between the two.

In the simple linear regression equation let b