2. 4.1 Tables and Graphs for the Relationship Between Two Variables Objectives: By the end of this section, I will be able to… 1) Construct and interpret crosstabulations for two categorical variables. 2) Construct and interpret clustered bar graphs for two categorical variables. 3) Construct and interpret scatterplots for two quantitative variables.

3. Section 4.1 Tables and Graphs for TWO Variables.

4. Crosstabulation Fancy word for a table. It is also known as a two-way table Helps you look for patterns in a data set.

5. Two-way Table Make a two way table to help you organize information. Who?Who?TOTAL What? What? TOTAL Question: Do you eat breakfast regularly?

6. Two-way Table MaleFemaleTOTAL Eats Breakfast Regularly Doesn’t Eat Breakfast Regularly TOTAL Question: Do you eat breakfast regularly?

7. Graphs for Crosstabulations

8. When to use? Crosstabulations and clustered bar graphs are useful for summarizing the relationship between CATEGORICAL variables.

9. What happens if you have QUANTITATIVE data? Use a SCATTERPLOT

10. SCATTER PLOTS graphs that display a relationship between two variables VARIABLES

11. What are the two variables?

13. Three Types of Scatterplot Relationships Positive Negative No relationship

14. ASSOCIATION Positive Relationship: Larger values of one variable tend to be associated with larger values of the other variable.

15. Negative Relationship: Larger values of one variable tend to be associated with smaller values of the other variable.

16. NO RELATIONSHIP

17. EXAMPLES

18. Question? Is there a relationship between how many digits you can type into your calculator and how fast you can do it?

19. Total Digits Typed Time (in seconds) x axis y axis