One-way ANOVA
§3.1
Rev 4.6 · reviewed Feb 2026One-way ANOVA
Compares a continuous outcome across three or more groups — the extension of the t-test. One line per group, values separated by commas.
Source formula: Fisher RA. Statistical Methods for Research Workers. 1925.
Table. Group summaries
| n | Mean | SD | |
|---|---|---|---|
| Group 1 | 5 | 5.24 | 0.27 |
| Group 2 | 5 | 6.22 | 0.24 |
| Group 3 | 5 | 5.94 | 0.23 |
Table. ANOVA
| Source | df | MS | F |
|---|---|---|---|
| Between groups | 2 | 1.27 | 20.89 |
| Within groups | 12 | 0.06 |
* Assumes roughly normal residuals and similar variances; with unequal variances prefer Welch's ANOVA. Fisher RA. Statistical Methods for Research Workers. 1925.
p (omnibus)
< 0.001▲
copyAt least one group mean differs (p < 0.001). ANOVA doesn't say which — follow with pairwise comparisons using a correction such as Tukey's HSD, and ask your statistician which contrast answers your question.
Understand what this is measuring