This tutorial was designed to help you understand the nature of the linear relationship captured by correlation and regression analysis.
This tutorial assumes that you know scales of measurement and the basic concepts used in correlation and regression. Its emphasis is on the visual representation of linear relationships. It does not address the statistical formulas used to calculate correlation and regression statistics.
A graph that shows the relationship between two variables is called a scatter diagram or scatter plot. In this tutorial, you will generate a series of scatter plots that show different types of relationships. You must have Microsoft Excel installed on your computer in order to do the tutorial. When you begin to work with the scatterplots, you will receive a message asking if you want to enable the "macro" function within Microsoft Excel. You must answer "yes" in order to do the tutorial.
Students enrolled in PSYC230 - Elementary Statistics - who wish to receive extra credit for doing the tutorial should submit the five scatter plots that you generate in this exercise to Dr. Bliwise. The scatter plots must be submitted before Exam #4 (Correlation and Regression).