1. Two-Way Between Groups ANOVA Chapter 14

2. Two-Way ANOVAs >Are used to evaluate effects of more than one IV on a DV >Can determine individual and combined effects of the IVs

3. Testing for Interactions >An interaction occurs when two IVs have an effect in combination that we do not see when looking at each IV individually >Two-Way ANOVAs include to nominal IVs and a scale DV >Factorial ANOVA uses one scale DV and at least two nominal IVs (factors) Factor: IV in a study with more than one IV

5. Why Use Two-Way ANOVAs >To evaluate effects of two IVs, it is more efficient to do a single study than two studies with one IV each. >Can explore interactions between variables

8. More ANOVA Vocabulary >Cell: box depicting a unique combination of levels of IVs in a factorial design >Main effect: When one IV influences the DV

9. Two Types of Interactions in ANOVA >Quantitative: interaction in which one IV exhibits strengthening or weakening of its effects at one or more levels of the other IV, but the direction of the effect does not change >Qualitative: interaction of two or more IVs in which one IV reverses its effect depending on the level of the other IV

10. What if both IVs influence the DV? >This is an interaction

22. Six Steps for Two-Way Between- Groups ANOVA >Step 1. Identify the populations, distribution, and assumptions. >Step 2. State the null and research hypotheses. >Step 3. Determine the characteristics of the comparison distribution. >Step 4. Determine critical values, or cutoffs. >Step 5. Calculate the test statistic. >Step 6. Make a decision.

23. df Formulae for ANOVAs

24. Determining the Cutoff Point

32. Effect Size for Two-Way ANOVA

34. Variations on ANOVA