Types of experiment Flashcards
What are the four types of experiment?
Laboratory
Field
Natural
Quasi
What is a laboratory experiment?
An experiment which takes place in a controlled environment within which the researcher manipulates the IV and records the effect on the DV while maintaining strict control of extraneous variables.
Strengths of lab experiments.
Lab experiments have high control over confounding and extraneous variables which means that the researcher can ensure that any effect on the dependent variable is likely to be the result of manipulation of the independent variable.
This high control also means that lab experiments can be easily replicated.
Limitations of lab experiments.
May lack generalisability as the lab environment may be rather artificial (low ecological validity) and not like everyday life (lacks mundane realism) . Behaviour observed therefore cannot always be generalised past the research setting.
Participants are usually aware that they are being tested in a lab experiment and this may give a rise to ‘unnatural behaviour’.
What is a field experiment?
An experiment that takes place in a natural setting within which the researcher manipulates the IV and records the DV.
Strengths of field experiments.
Field experiments have higher mundane realism than lab experiments because the environment is more natural. Field experiments may produce behaviour that is more valid and authentic.
Limitations of field experiments.
As the experiment is more natural than a lab experiment, there is reduced control over confounding and extraneous variables. This means the cause and effect between the IV and DV in field studies may be much more difficult to establish.
There are also important ethical issues if participants are unaware they are being studied.
What is a natural experiment?
An experiment where the change in IV is not brought about by the researcher and would have happened if the researcher had not been there. The researcher records the effect on the DV.
Give an example of conditions for a natural experiment.
A natural disaster.
Strengths of natural experiments.
Provide opportunities for research that may not otherwise be undertaken for practical or ethical reasons.
They have high external validity because they involve the study of real-world issues and problems as they happen.
Limitations of natural experiments.
A naturally occurring event may only happen very rarely which reduces the opportunities for research and may limit the scope for generalising findings to other similar situations.
Participants may not be randomly allocated to experimental conditions so the researcher may be less sure whether the UV affected the DV.
What is a quasi-experiment?
A study that is almost an experiment but lacks key ingredients. The IV has not been determined by anyone the variables simply just exist e.g being old or young.
Strengths of quasi-experiments.
Often carried out under controlled conditions and therefore share some strengths of lab experiments.
Limitations of quasi-experiments.
Cannot randomly allocate participants to conditions so may be confounding variables.
