Experimental Design Flashcards
What is independent group designs?
-It is when two separate groups of participants experience two different conditions of the experiment.
What are the advantages of an independent groups design?
-Order effects are not a problem due to participants going through one condition only therefore their behaviours wont change and they are less likely going to guess the aim, get bored or get better at the task.
What are the disadvantages of independent groups?
- as there are different participants in each condition there will be individual differences such as age, gender, intelligence. Therefore we cannot be sure that the DV is the cause and effect of the IV as participant variables and individual differences in the participants might have caused it.
- Independent groups design is less economical than repeated measures design as twice as many participants are needed as each participant only takes part in one condition.
What is repeated measures?
An experimental design where both participants experience both conditions in the experiment
What are the advantages of repeated measures?
- participant variables and individual differences no longer is a problem and will not affect the DV as participants take part in both conditions.
- It is cost effective and economical as fewer participants are required compared to independent groups.
What are the disadvantages of repeated measures?
-Order effects becomes an issue as a result of participants going through both conditions and this may lead to them guessing the aim, getting better, or bored at the task which will affect the DV.
How do you deal with participant variables/individual differences and order effects
Participant variables=random allocation
Order effects=counterbalancing
What is matched pairs design?
-it is an experimental design where participants are paired up and matched with another participant taking part in opposite conditions on a specific participant variable (examples age, gender, intelligence)
What are the advantages of matched pairs?
- participants take part in one condition only so order effects is not an issue so the order or demand characteristics should not affect the DV.
- individual differences wont affect the DV as a result of participants being matched on a certain participant variable.
What are the Disadvantages of matched pairs design?
- It is very expensive and time consuming to match participants on specific participant variables so it is less economical than other experimental design.
- Participants can never be matched exactly even when identical twins are used, there will still be important differences between them and that may affect the DV.
