Correlation

Correlation is a relationship or dependency that exists between two variables.

If a correlation exists, it is said that the variables are correlated or there is a correlation between them.


Types of Correlation

Positive Correlation

A positive correlation occurs when an increase in one variable increases the other variable.

The line corresponding to the scatter plot is an increasing line.

Positive Correlation

Negative Correlation

A negative correlation occurs when an increase in one variable decreases the other.

The line corresponding to the scatter plot is a decreasing line.

Negative Correlation

No Correlation

No correlation occurs when there is no linear dependency between the variables.

No Correlation


Perfect Correlation

A perfect correlation occurs when there is a funcional dependency between the variables.

In this case all the points are in a straight line.

Perfect Correlation


Strong Correlation

A correlation is stronger the closer the points are located to one another on the line.

Strong Correlation

Weak Correlation

A correlation is weaker the farther apart the points are located to one another on the line.

Weak Correlation