方差分析F统计量计算器 — 公式
One-Way ANOVA F-Test
ANOVA tests whether the means of two or more groups are significantly different by comparing between-group variance to within-group variance.
Formula
F = MSB / MSW
where MSB = SSB/(k-1) is the mean square between groups and MSW = SSW/(N-k) is the mean square within groups. A large F indicates that group means differ more than expected by random chance.
计算示例
MSB = 120, MSW = 30, k = 4 groups, N = 40 total observations.
- F = 120 / 30 = 4.000
- df1 = 4 - 1 = 3, df2 = 40 - 4 = 36
- Critical F(3,36) at alpha=0.05 ≈ 2.87
- F = 4.0 > 2.87, so groups differ significantly