How to use
- Enter one group per line using a label plus values, such as
Control: 5.1 4.9 5.0. - Run the one-way ANOVA and read the ANOVA table together with eta-squared and the grouped summary chart.
- If the overall F test matters for follow-up decisions, move to a post-hoc workflow outside this page because pairwise follow-up is not included here yet.
Wave 2 statistics expansion
One-way ANOVA from grouped raw values
Box view emphasizes median, quartiles, and spread so you can spot overlap before reading the F statistic.
Use label: values, label, value, value, or tab-separated input. If your decimals use commas, separate values with spaces or semicolons.
Run a calculation to see the ANOVA summary.
ANOVA table
| Source | SS | df | MS | F | p-value |
|---|
Group summary
| Group | n | Mean | SD | Min | Max |
|---|
Grouped summary chart
The chart follows the group order from your pasted input. Read it before interpreting the p-value so spread and overlap stay visible.
Run a calculation to render the summary chart.
What one-way ANOVA does, and what it does not do
One-way ANOVA answers a narrow question: is the variation between group means large relative to the variation inside groups? That is why the ANOVA table separates between-group and within-group sums of squares before forming the F statistic.
Two groups reduce to the equal-variance t-test
If you only have 2 independent groups, one-way ANOVA and the equal-variance two-sample t-test carry the same significance result because the ANOVA F statistic is just the squared t statistic. This page still works, but the dedicated t-test calculator is easier when the design really has only 2 groups.
Effect size belongs next to the F test
After you read the ANOVA table, use the effect-size calculator when you want eta-squared in a page dedicated to practical magnitude rather than only statistical significance.
Post-hoc comparisons are not included in this release
A significant F test tells you that at least one mean differs, not which pair differs. This first release stops at the overall test and effect size, so run a post-hoc method elsewhere if the next decision depends on pairwise differences.
Frequently asked questions
When should I use one-way ANOVA?
Use one-way ANOVA when you want to compare the mean outcome across 3 or more independent groups with one grouping factor. If you only have 2 groups, the equal-variance two-sample t-test gives the same p-value because F = t squared.
Why does this page mention post-hoc tests?
ANOVA tells you whether at least one group mean differs, but it does not identify which pairs differ. This first release stops at the overall F test, so you still need a post-hoc procedure outside this page when pairwise follow-up matters.
What does eta-squared mean?
Eta-squared is a simple effect-size measure for one-way ANOVA. It estimates the share of total variance explained by group membership in this sample, so it complements the p-value with a magnitude view.
Does the share URL include my pasted data?
No. The share URL stores only lightweight display settings such as the summary chart view. The raw grouped data stays in your browser.
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