Spearman's rank correlation coefficient
For example, for the data that we did above,  was 0.8. So this means that there is a positive correlation. Because it is close to 1, it means that the link is strong between the two sets of data. So, we can say that those two sets of data are linked, and go up together. If it was −0.8, we could say it was linked and as one goes up, the other goes down.