Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Variance between samples measures the dispersion of sample means around the overall mean in ANOVA. It quantifies how much the group means differ from each other.
5 Must Know Facts For Your Next Test
Variance between samples is an essential component in calculating the F-ratio.
It helps determine whether there are significant differences between group means.
Higher variance between samples indicates greater differences among group means.
It is contrasted with variance within samples, which measures variability within individual groups.
The formula for variance between samples is $MSB = \dfrac{SSB}{df_B}$, where $SSB$ is the sum of squares between groups and $df_B$ is the degrees of freedom between groups.
Review Questions
Related terms
F-Ratio: A statistic used in ANOVA to compare variances and determine if there are significant differences among group means.
Sum of Squares Between (SSB): The total squared deviation of each group's mean from the overall mean, weighted by sample size.
Degrees of Freedom Between (df_B): The number of independent values or quantities which can be assigned to a statistical distribution, calculated as the number of groups minus one.