Research methods- Lab, feild and natural experiments Flashcards
What three things do all 3 experiment types have in common?
-an independent variable (I.V.) which is manipulated or a naturally occurring variable
Dependent variable (D.V.) which is measured
-there will be at least two conditions in which participants produce data
What are lab experiments?
Experiments are conducted under controlled conditions, in which the researcher deliberately changes something (I.V.) to see the effect of this on something else (D.V.).
What are the two strengths of lab experiments?
Control – lab experiments have a high degree of control over the environment & other extraneous variables which means that the researcher can accurately assess the effects of the I.V., so it has higher internal validity.
Replicable – due to the researcher’s high levels of control, research procedures can be repeated so that the reliability of results can be checked
What is the limitation of lab experiments?
Lacks ecological validity – due to the involvement of the researcher in manipulating and controlling variables, findings cannot be easily generalised to other (real life) settings, resulting in poor external validity
What are field experiments?
Carried out in a natural setting, in which the researcher manipulates something (I.V.) to see the effect of this on something else (D.V.)
What is the strength of field experiments?
Validity – field experiments have some degree of control but also are conducted in a natural environment, so can be seen to have reasonable internal and external validity.
What is the limitation of field experiments?
Less control than in lab experiments and therefore extraneous variables are more likely to distort findings so internal validity is likely to be lower.
What are natural/quasi-experiments?
carried out in a natural setting, in which the researcher measures the effect of something which is to see the effect of this on something else (D.V.). Note that in this case there is no deliberate manipulation of a variable; this already naturally changing, which means the research is merely measuring the effect of something that is already happening
What is the strength of natural/quasi-experiments?
High ecological validity – due to the lack of involvement of the researcher; variables are naturally occurring so findings can be easily generalised to other (real life) settings, resulting in high external validity.
What are some limitations of natural/quasi-experiments?
Lack of control – natural experiments have no control over the environment & other extraneous variables which means that the researcher cannot always accurately assess the effects of the I.V., so it has low internal validity.
Not replicable – due to the researcher’s lack of control, research procedures cannot be repeated so the reliability of results cannot be checked.
