Kostenloser F-Statistic Rechner
Berechnen Sie den F-statistic for comparing two variances. Kostenloser F-test Rechner mit degrees of freedom.
F-Statistic
1.562500
F-Statistic vs Sample Variance 1 (larger)
Formel
## How to Calculate the F-Statistic ### Formula **F = s1^2 / s2^2** The F-statistic is the ratio of two sample variances, with the larger variance in the numerator by convention. Under the null hypothesis of equal population variances, F follows an F-distribution with df1 = n1-1 and df2 = n2-1. F-values near 1 suggest equal variances.
Lösungsbeispiel
Group 1: variance = 25, n = 20. Group 2: variance = 16, n = 25.
- 01F = 25 / 16 = 1.5625
- 02df1 = 20 - 1 = 19
- 03df2 = 25 - 1 = 24
- 04SD ratio = sqrt(1.5625) = 1.25
- 05Compare F = 1.5625 to F-distribution(19, 24)
Häufig Gestellte Fragen
Why put the larger variance in the numerator?
By convention, this ensures F >= 1 and simplifies looking up critical values. Some procedures test both tails, in which case the order matters less.
What does F = 1 mean?
F = 1 means the two sample variances are identical, providing no evidence that the population variances differ.
How is the F-test used in ANOVA?
In ANOVA, the F-statistic is the ratio of between-group variance to within-group variance. A large F indicates that group means differ more than expected from random variation alone.
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