- advantages and disadvantages of different experiments
- confounding variables
- independent and dependent variables
Is the experimental design the one that states whether an experiment is independent measures, repeated measures or matched pairs?
Independent measures - each group does one of the conditions (e.g. one group revises before an exam, the other group doesnt). The main disadvantage of this experiment is that there maybe individual differences between the participants which effect the results (e.g. IQ). However, demand characteristics are less likely as the participants only see one condition.
Repeated measures - a group will do both conditions (e.g. they do the test without revising, then they revise and do a similar test to see if the scores have improved). The main advantage of this design is that individual differences do not effect the results as it is the same individuals taking both conditions. However, the participants are seeing both conditions so maybe able to guess the purpose of the experiment (demand characteristics).
Matched-pairs - 2 groups of participants who are similar to each other. The two groups will do the different conditions. Main advantage is that you almost illiminate individual differences as you are ensuring that both groups are similar to each other (e.g. have the same range of IQs in each group). Also demand characteristics are less likely to occur as an individual only does one condition. The main disadvantage is that it is very difficult to get two groups of people who are very similar to one and other.
Hope that helps a bit. Good luck in your exam.