In this chapter, we discussed correlation. Correlation is a statistical measure that can be used to inspect how a pair of variables are related. Understanding these relationships can help you to decide the most important features from a set of variables. Once we understand the correlation, we can use it to make better predictions. The higher the relationship between the variables, the higher the accuracy of the prediction. Since correlation is of higher importance, in this chapter, we have covered several methods of correlation and the different types of analysis, including univariate analysis, bivariate analysis, and multivariate analysis. 

In the next chapter, we will take a closer look at time series analysis. We will use several real-life databases, including time series analysis, in order to perform exploratory data analysis.