Click on the following links. Please note these will open in a new window.

Correlations, Reliability and Validity, and Linear Regression

It explains how correlation describes a relationship between two variables.

Pearson Product–Moment Correlation – Laerd Statistics

It explains how a Pearson product–moment correlation attempts to draw a line of best fit through the data of two variables, and the Pearson correlation coefficient, r, indicates how far away all these data points are to this line of best fit (i.e., how well the data points fit this new model/line of best fit).