Two-Way ANOVA Using SPSS Statistics
The Two-Way ANOVA is a statistical test used to determine the effect of two nominal predictor variables on a continuous outcome variable. This tutorial provides a step-by-step guide to performing a Two-Way ANOVA using SPSS Statistics.
Step 1: Load Your Data
Begin by opening SPSS Statistics and loading your dataset. Ensure your data is properly formatted, with no missing values. For this example, we have a dataset with two independent variables (IVs) and one dependent variable (DV).
Step 2: Set Up the ANOVA
Navigate to Analyze > General Linear Model > Univariate…. Move your DV to the Dependent Variable box and both IVs to the Fixed Factors box.
Step 3: Configure Options
Click on Options and select Descriptive statistics, Estimates of effect size, and Homogeneity tests. Click Continue and then OK to run the analysis.
Step 4: Interpret the Results
SPSS will produce several tables. Key tables include the Descriptive Statistics table, the Levene’s Test of Equality of Error Variances table, and the Tests of Between-Subjects Effects table.
Descriptive Statistics Table
| Group | N | Mean | Std. Deviation |
|---|---|---|---|
| Group 1 | 30 | 23.45 | 4.56 |
| Group 2 | 30 | 25.67 | 5.34 |
Levene’s Test of Equality of Error Variances
| F | df1 | df2 | Sig. |
|---|---|---|---|
| 1.234 | 1 | 58 | 0.567 |
Tests of Between-Subjects Effects
| Source | Type III Sum of Squares | df | Mean Square | F | Sig. | Partial Eta Squared |
|---|---|---|---|---|---|---|
| IV1 | 123.456 | 1 | 123.456 | 4.567 | 0.034 | 0.073 |
| IV2 | 78.910 | 1 | 78.910 | 2.345 | 0.130 | 0.039 |
| IV1 * IV2 | 56.789 | 1 | 56.789 | 1.890 | 0.175 | 0.032 |
Discussion
The Two-Way ANOVA results indicate that IV1 has a significant effect on the DV, F(1, 58) = 4.567, p = .034, η² = .073. However, IV2 does not have a significant effect, F(1, 58) = 2.345, p = .130, η² = .039. Additionally, there is no significant interaction effect between IV1 and IV2, F(1, 58) = 1.890, p = .175, η² = .032.
Conclusion
This tutorial demonstrated how to perform a Two-Way ANOVA using SPSS Statistics. Understanding these steps can help you analyze the impact of two independent variables on a dependent variable, providing valuable insights for your research.
Further Reading
- Mastering Paired Samples t-Tests in SPSS
- How to Perform a One-Sample t-Test in SPSS
- Understanding Correlation Analysis
- Mastering SPSS: Descriptive Statistics
- SPSS for Beginners: Adding and Analyzing Data
- Comprehensive Guide to Using SPSS for Data Analysis
- Mastering SPSS: Independent Samples t-Test
- Multiple Regression Using SPSS
- Mastering SPSS: Working with Variables
- Chi-Square Test for Association Using SPSS
- Friedman Test Using SPSS Statistics
- Mastering SPSS: Linear Regression Using SPSS
- Creating a Scatterplot Using SPSS
- Multiple Regression Using SPSS
- Mastering SPSS: Kendall’s Tau-b Using SPSS