Mixed Designs ANOVA Flashcards
•When there is more than one factor, we can have a…
mixed (or split plot) design
•One or more repeated measures
•One or more between subjects measures
The Mixed or Split Plot design combines features of
both between groups and within subjects designs.
•That is each level of factor A contains a different groups of randomly assigned subjects.
•On the other hand, each level of factor B at any given level of factor A contains the same subjects
•No such thing as a one factor mixed design.
A number of assumptions are made by ANOVA that should be…
tested prior to analysis
Significant results often require…
Further analysis
Both planned and unplanned comparisons can be
Conducted
Interactions nearly always require
Further analysis
A failure to find a significant result may be due to lack of
•statistical power
ANOVA is a parametric statistical technique for testing…
the differences between means
ANOVA can be used to analyse both
single factor and multifactorial designs.
Anova can be used to analyse differences in between
ANOVA , within subjects and mixed designs.
Pre analysis of checks
- Homogeneity of Variance
- For a mixed design it is necessary to check in a variety of different ways
- Overall - Box’s M
- Within subjects - Mauchly’s W
- Between groups - Levene’s test
- Normality
- This can also be tested in a number of ways
- SPSS conduct’s these tests.
Partitioning the variance is done as for a…
standard ANOVA with small variations
For the effects of interest
- A between groups effect is estimated
- A within subjects effect is estimated
- An interaction effect is estimated
For the error terms
- A between subjects error is used for the between groups effect
- Within subjects error term used for the within subjects effect
- The within subjects error term is also used for the interaction effect since this includes a within subject component.
