1. Scatter Diagrams

2. Scatter Diagram Page 195 Tool Book WHAT is a scatter diagram? –A picture of the correlation between two factors over time. –The more data - the more reliable –The closer the data resembles a straight line, the higher the correlation to each other. –Diagrams may be positive, negative or show no correlation.

3. Positive Correlation

4. Negative Correlation

5. No Correlation

6. Correlation?

9. Examples of Scatter Diagram Patient Age Vs. Recovery Time

15. Cautions! There is a maxim in statistics that says, "Correlation does not imply causality." In other words, your scatter plot may show that a relationship exists, but it does not and cannot prove that one variable is causing the other. There could be a third factor involved which is causing both, some other systemic cause, or the apparent relationship could just be a fluke. Nevertheless, the scatter plot can give you a clue that two things might be related, and if so, how they move together.