Laboratory Experiments are controlled and scientific. Lab experiments are conducted in an artificial setting, e.g. Milgrams study.
- experimenters have a high level of control so the effects of confounding variables are minimised.
- Replication. Lab experiments can easily be replicated by other researches, this enables them to check the results.
- Casual relationships can be identified. This is when an experimenter is able to establish whether one variable causes change in another.
- This method is artificial, therefore it can lack ecological validity.
- Demand characteristics are more likely to occur in lab experiments. This is when participants respond according to what they think is being investigated, this can bias the results.
- Lab experiments breech certain ethics, for instance deception, this occurs because making informed consent can be difficult, (e.g. cause people to act under demand characteristics).
Field Experiments are conducted outside the laboratory. In this type of experiment behaviour is measured in an natural environment. A key variable is altered so that it's effect can be measured.
- Casual relationships can be identified however it is very difficult to manipulate the key variables in a Natural setting.
- Field experiments are less artificial compared to lab studies, this means they have a higher ecological validity because they can relate more to real life.
- Demand characters are less likely to occur. They are avoided if participants do not know they are involved in a study.
- There is less control in field experiments because confounding variables are more likely in a natural environment.
- Field experiments breech certain ethics. Participants who did not agree to take part may experience distress, this means they will need to be debriefed.
A Natural Experiment is a study that measures variables which are not directly manipulated by the researcher. For instance comparing behaviour in a single-sex girls school and a mixed school.
- reduction of demand characteristics because participants may be less conscious that they are involved in an experiment therefore demand characteristics may be avoided.