ANOVAs Flashcards
Single-Factor, Multi-Level Design
has only one IV; IV must have more than two levels of IV.
Factorial Design
includes 2+ Factors (each allowed multiple levels as well) and ensures they all interact/cross over each other for testing. Establish whether IVs have a main effect, and establish whether there was an interaction.
Multi-Level Design Use
When data is organized at more than 1 level, but there is only one IV being tested.
Factorial Design Use
Factorial designs are better able to capture real-life causal complexity than are designs that manipulate only one IV.
What is the advantage of conducting a one-way ANOVA vs. multiple t-tests?
Primary advantage over running multiple t-tests is that it avoids alpha inflation (the increased chance of making a Type I error when running multiple t-tests)
What happens to your F-ratio as your treatment effect increases?
Increasing the mean differences between treatments produces a larger F-ratio.
Factorial Design Advantages
Better able to capture real-life complexities.
Factorial Design Disadvantages
Every time variables are added, the experiment becomes more complicated with interpretations, higher participant count needed, more testing, etc…
Factorial Design
Includes two or more factors (Ivs), each factor can have 2+ levels, with everything crossing/interacting with each other.
2x4x6x2
4 Ivs: 2 levels, 4 levels, 6 levels, 2 levels
Main Effect
The effect of one independent variable on the dependent variable in isolation.
Interaction
A relationship between two or more systems, people, or groups that results in mutual or reciprocal influence (combined effects).
Post Hoc Test
Analysis performed on 3+ groups to determine exactly which groups differ from each other.
What does an interaction on factorial graph look like?
If the lines are parallel: no interaction, anything else: interaction (any factor on the x-axis)
What does a main effect on a chart look like?
No difference in marginal means: no main effect, any difference; main effect present
