Experiment designs Flashcards
Repeated measures
Same participants used in each condition. Participants experience all conditions
Repeated measures strength i
Unlike independent groups, where different participants are used in each condition, strength is that it removes individual differences
Which are differences in the ability of participants that may affect their performance in each condition
This is because the same participants are used in each condition, meaning that participants of exactly the same ability level are used
Therefore, any differences are likely to be due to the changes in conditions rather than changes in the participants
Repeated measures strength V
Unlike independent groups, where different participants are used in each condition, a strength is that it clearly shows the effect of the IV on the DV
This is due to the fact that the same participants are used in each condition
Meaning its possible to be more certain that the only thing affecting the DV is the change in the IV and not differences in participants
Repeated measures limitations d
Unlike independent groups, where different participants are used in each condition, a limitation is that demand characteristics are more likely
This is when participants perceive the demands of the experiment and act accordingly, lowering the internal validity of research because of the change in participants natural behaviour
This is because the same participants are used in each condition, making them more able to perceive the experiments demands
Repeated measures limitation o
Unlike independent groups, where different participants are used in each condition, a limitation is that order effects become likely
Which are factors such as practice (learning effect) or tiredness (fatigue effect) that can affect the performance of participants in the second condition
This is because the same participants are used in each condition, making these factors more likely
Independent groups
Different participant are used in each conditions
Participants only experience one condition
Independent groups strength o
Unlike repeated measures, where participants experience all conditions, strength is that it removes the possibility of order effects
Which are factors such as practice (learning effect) or tiredness (fatigue effect) that can affect the performance of participants in the second condition
This is because the different participants are used in each condition, meaning no participant ever repeats a condition, making these factors impossible
Independent groups strength d
Unlike repeated measures , where participants experience all conditions, strength is that demand characterises are less likely
These occur when participants perceive the demands of the experience that and act accordingly, lowering the internal validity of research because of the change in participants natural behaviour
This is because different participants are used in each condition, making them less able to perceive the experimenters demands
Independent groups limitation i
Unlike repeated measures, where participants experience all conditions, a limitation is that it may suffer from the effect of individual differences
Which are differences in the ability of participants that may affect their performance in each condition
This is because the different participants used in each condition may have different abilities for the characteristic being tested, which is likely to affect the validity of research
Matched pairs strengths i
Unlike independent groups, where different participants are used in each conditions, os that that it limits the impact of individual differences
Which are differences in the ability of participants that may affect their performance in each condition
This is because participants were matched in each condition, meaning that participants of a very similar ability level are used in each condition
Independent groups limitation p
Unlike repeated measures, where participants experience all conditions, is that it requires twice as many participants as a repeated measures design
Which may negatively affect the cost and practicality of research
This is because different participants are used in each condition, meaning twice as many participants need to be recruited to produce the same amount of data to that in a repeated measures design
Matched pairs
Different, but similar participants are used in each condition
An effort is made to match the participants in each condition on factors such as age, sex, abilities which are relevant to the study
Matched pairs strengths o
Unlike repeated measures, where participants experience all conditions, it removes the possibility of order effects
Which are factors such as practice (learning effect) or tiredness (fatigue effect) that can affect the performance of participants in the second condition
this is because the different participants are used in each condition, meaning no participant ever repeats a condition, making these factors impossible
matched pairs strength d
unlike repeated measures, where participants experience all conditions, a strength of a matched pairs design is that demand characteristics are less likely
these occur when participants perceive the demands of the experiment and act accordingly, lowering the internal validity of research because of the change in participants natural behaviour
this is because similar but different participants are used in each condition, making them less able to perceive the experimenters demands
matched pairs limitation i
may suffer from individual differences even though an effort has been made to match participants in each condition
these are differences in the ability of participants that may affect their performance in each condition
this is because matching is difficult that participants can never be truly matched
equally, participants may be matched for the wrong variable, meaning another (unmatched) variable may affect the validity of research
