What do you mean by correlation?
Correlation means the extent to which the two variables have a linear relationship with each other. It is a statistical technique which can show how strongly variables are related to each other. It is a scaled version of covariance and values ranges from -1 to +1.
It can be calculated as
Ways to detect Correlation between variables:
- Graphical Method: The pattern of scatter plot indicates the relationship between variables. The relationship can be linear or non-linear.
- Scatter plot shows the relationship between two variables but does not indicates the strength of relationship amongst them.
- Non-graphical method: Build the correlation matrix to understand the strength between variables. Correlation varies between -1 and +1.
- -1: Perfect negative linear correlation
- +1: Perfect positive linear correlation
- 0: No correlation