Experiments Flashcards
What is a laboratory experiment?
An experiment that takes place in a controlled environment where extraneous variables are controlled and the researcher manipulates the IV and records the effect it has on the DV.
What are the advantages of a laboratory experiment?
- Extraneous variables are controlled therefore the IV is the cause and effect of the DV which can be established which will increase the validity of the findings.
- Replication is possible as all the extraneous variables are controlled, therefore we can see if the findings are valid and reliable and not just a one off.
What are the disadvantages of a laboratory experiment?
- It lacks ecological validity as a result of it being conducted in an artificial setting therefore we cannot generalise the findings to real life.
- Demand characteristics is more likely to occur as a result of participants knowing they are being investigated therefore they are more likely going to guess the aim of the experiment which will affect the DV which will decrease the validity of the findings.
What are field experiments?
-An experiment that takes place in a natural eating where the researcher manipulates the IV and records the effect on the DV.
What are the advantages of field experiments?
- It has high ecological validity as a result of it being conducted in a natural setting therefore the findings can be generalised to real life this is due to individuals producing natural behaviour they would usually produce in their familiar environments.
- People are less likely going to guess the aim of the experiment as they probably will not know they are being investigated therefore this reduces demand characteristics which increases the validity of the findings.
What are the disadvantages of field experiments?
- The lack of control of extraneous variables means the extraneous variables can affect the the DV and we cannot establish that the IV is the cause and effect of the DV.
- Ethical issues can be a concern as participants usually do not know if they are being studied which breaches informed consent to being studied.
What is a natural experiment?
-An experiment where the IV is occurring naturally and is not manipulated by the researcher. The researcher just takes advantage of the pre existing IV. The DV would occur even if the researcher did not take advantage of the IV. It could also be investigated in an artificial setting.
What are the advantages of a natural experiment?
- High ecological validity as it involves real life studies of real life issues.
- It allows a researcher to investigate phenomenons that rarely occur or that may not be undertaken for practical ethical reasons
What are the disadvantages of a natural experiment?
- A naturally occurring event rarely happens therefore this limits the opportunities for research and reduces the generalisability to apply the findings to similar situations
- Participants may not be randomly allocated to experimental conditions so individual differences and participant variables can affect the DV therefore we cannot establish the IV is the cause and effect of the DV.
What is a Quasi experiment?
-The IV has not been determined by anyone it is naturally occurring within the participant and the IV cannot be manipulated.
What are advantages of a Quasi experiment?
-under controlled conditions they have the same strengths of a lab experiment
What are the disadvantages of Quasi experiments?
- Lacks ecological validity if conducted under controlled settings
- Participants cannot be randomly allocated therefore participant variables can turn into confounding variables and affect the DV therefore decreasing the validity of the findings.
What are investigator effects?
It is a cue other than the IV from an investigator that encourages certain behaviour in participants which might lead to a fulfilment of the investigators expectations.
What ways can investigator effect occur?
- Non verbal communication: such as there actions like raising an eyebrow can make a participant change their behaviour
- Physical characteristic: The appearance of a researcher and such physical characteristics as their gender will influence the behavioural response of the participant. This means that the behaviour is a product of the situation and not the IV which decreases the validity of the findings.
- Bias in interpretation of data: A researcher can affect the results reported from a piece of research by interpreting it in a biased way this will occur if they are collecting subjective data
