ANOVA Decision Tool
Instantly interpret your ANOVA results, determine significance, and get an APA-style write-up.
Check Your ANOVA Significance
What Does an ANOVA Test Do?
Analysis of Variance (ANOVA) is a statistical method used to test differences between two or more means. It analyzes variances to determine if the means of different groups are significantly different from each other.
You typically use a One-Way ANOVA when you have one independent categorical variable (with three or more groups) and one dependent continuous variable. For example, comparing the test scores of students taught using three different teaching methods.
Interpreting Your Result
When you run an ANOVA, you are testing a null hypothesis (H₀) and an alternative hypothesis (H₁):
- Null Hypothesis (H₀): All group means are equal. (There is no difference).
- Alternative Hypothesis (H₁): At least one group mean is different from the rest.
If your p-value is less than your significance level (α), you reject the null hypothesis. This indicates that a significant difference exists somewhere among your groups.
What Happens Next? (Post-Hoc Tests)
If your ANOVA result is not statistically significant, your analysis stops there. You conclude there's no evidence of a difference.
However, if your result is statistically significant, the ANOVA only tells you that at least one group is different—it does not tell you which specific groups differ. To find out exactly where the differences lie, you must conduct Post-Hoc Tests (like Tukey's HSD or Bonferroni corrections).