Definitions for Design of Experiments
Each participant is exposed to only one condition. One group is exposed to condition of smiling, while another group is exposed to condition of not smiling.
One of the main advantages of this group is that it avoids practice and fatigue effect as people are restricted to one condition only. While, disadvantage is that a large number of participants is required. Individual differences can give rise to high variability in the moods. Researcher does not have much control over confounding variables.
Here same participant takes part in each condition of independent variable. That is both the conditions, smiling and not smiling has same participants.
One of the main advantages is that fewer people are required. Disadvantages include order effects. That is performance on second condition might be affected cause of practice or fatigue effect.
Each participant of pair is randomly assigned to experimental and control group.
- Matched pairs
Main advantage is that it avoids order effects and hence counter balancing is not necessary and it requires less participants. While disadvantage is that it required a lot of time to match pairs. It is also impossible to match people exactly.