Session 5b Flashcards
Two-way ANOVA Statistically examines the effects of:
Two factors of interest on the DV Main effects (row and column)
Interaction between the diferent levels of these two factors
Interaction effect
Prior requirements/assumptions of 2 way anova
The population distribution of the DV is normal within each group The variance of the population distributions are equal for each group (homogeneity of variance assumption)
Independence of observations
way ANOVA: Basic concepts
- Divides the variance observed in data into different parts resulting from different sources
2 Assesses the relative magnitude of the different parts of variance
3 Examines whether a particular part of the variance is greater than
expectation under the null hypothesis
what does ANOVA stand for
ANalysis Of VAriance
Total SS (=variation) can be divided into two parts
SST =SSM +SSR
what is SST
= Total variation
what is SSM
= Model (Between-group) variation
what is SSR
= Residual (Within-group) variation
SSM can be divided further into what
SSA
SSB
SSAxB
what is SSA
Variation between means for Factor A
what is SSB:
Variation between means for Factor B
what is SSA×B:
Variation between cell means
