๐ŸŽฒintro to statistics review

F distribution

Written by the Fiveable Content Team โ€ข Last updated September 2025
Written by the Fiveable Content Team โ€ข Last updated September 2025

Definition

The F distribution is a continuous probability distribution that arises frequently as the null distribution of a test statistic, especially in ANOVA. It is defined by two parameters: the degrees of freedom for the numerator and the denominator.

5 Must Know Facts For Your Next Test

  1. The F distribution is used to compare variances between groups.
  2. It is asymmetric and skewed to the right, becoming more symmetric as sample sizes increase.
  3. Degrees of freedom for the numerator come from the number of groups minus one, while degrees of freedom for the denominator come from total observations minus number of groups.
  4. The critical values for an F-test are found using F-tables or statistical software.
  5. In ANOVA, a high F-ratio suggests that at least one group mean is different from others.

Review Questions

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