Pearson formula takes on many forms but it is commonly used for calculating the correlation between two sets of data. There are two arrays of data for which the Pearson formula is used. If there are two sets of data x and y then there can be a negative, positive or no correlation between the two sets. Therefore the type of data that is used for applying Pearson formula is two arrays data. For numerical example click on the link:

Pearson data example

Pearson data example