Correlation and Regression

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 the Plots Exercise, you will generate a series of scatter plots that show different types of relationships.

Why Is This Important?
Correlation and regression are widely used statistics in psychological research. They summarize the type and strength of the relationship between two variables and are very popular in survey research.