anova Flashcards
(6 cards)
1
Q
what is analysis of variance ?
A
extension of the t test and allows us to test whether 3 or more population means are the same without reducing power
2
Q
what are the assumptions of anova?
A
- scores were randomly sampled
- roughly normal distribution
- roughly equal number of ppts in the group
- roughly equal variance
3
Q
what is the basis of the test ?
A
analysis of the variance is a way to compare multiple conditions in a single powerful test
it was invented by fisher
it compares the amount of variance explained by our experiment with the variance that is unexplained
4
Q
what is the variance between groups ANOVA?
A
explained variance is the variance between groups
the unexplained is the variance within a group
5
Q
what is the anova formula?
A
the effect / the noise
6
Q
degrees of freedom and anova?
A
- degrees of freedom between conditions
- residual degrees of freedom
- anova critical values require 2d.f values one for each aspect of variance
