research methods Flashcards
What is independent groups design?
One group does condition A, one group does condition B.
Participants randomly allocated to experimental groups.
What are the advantages of independent groups design?
No order effects e.g. ppts don’t become bored/tired.
Will not guess aim - ppts only tested once, so unlikely to guess aim. So behaviour more natural.
What are the disadvantages of independent groups design?
Participant variables - The participants in the two groups are different, acts as EV. May reduce validity of study.
More participants - Need to find twice as many participants.
What is repeated measures design?
Same person in both conditions. Advantages and disadvantages are opposite of independent groups design.
What is matched pairs design?
Two groups of participants are used but they are related to each other by being paired on certain participant variables that matter to the experiment e.g. two women in their 20s.
What are the advantages of matched pairs design?
Participant variables reduced - because participants matched. This enhances validity of results.
No order effects - Participants only tested once so no fatigue effects etc
What are the disadvantages of matched pairs design?
Matching is not perfect - Matching can’t control all relevant variables. May not address all participant variables.
More participants - Need twice as many participants.
What is a pilot study?
A pilot study is an initial run through of the procedures to be used in an investigation.
What are the aims of running a pilot study?
A pilot study helps foresee any problems with the experiment, e.g. if the design works, if the ppts understand the instructions.
Problems can be tackled before running the main study.
Why does research need to be highly controlled?
To avoid the effects of extraneous variables.
What are extraneous variables?
Any variable you’re not interested in studying that could also have some effect on the dependent variable.
What is counterbalancing?
Counterbalancing is mixing up the order of the tasks, which can solve order effects in repeated measures design.
E.g. half the ppts do task with audience first and then without, other half do without first.
Any order effects would be equal across conditions and so would cancel each other out.
What is random allocation?
Random allocation (e.g. drawing names out of a hat) means everyone has an equal chance of doing either condition.
In a study, if there are more men in one group than the other, the results may be based on gender rather than IV.
Random allocation should ensure groups are not biased on key variables.
What are standardised instructions?
Standardised instructions should insure the experimenters act in the same way with all participants.
Everything should be as similar as possible for all the participants.
What is the independent variable?
The thing that is different between the two conditions.
It has been manipulated by the researcher.
What is the dependent variable?
What is being measured by the researcher.
What is a confounding variable?
If we do not eliminate or control extraneous variables, they become confounding variables - i.e. they affect the results (DV)
What is the experimental method?
The manipulation of the independent variable to measure the effect on a dependent variable.
What are situational variables?
Features of a research situation that may influence the participant’s behaviour and therefore act as EVs.
Include time of day, noise, order effects and investigator effects.
What are order effects?
The order of the conditions having an effect on the participants’ behavior e.g. the participants perform worse in the second condition because they were tired, not because of the IV.
What are investigator effects?
Any cues (other than than the IV) from an investigator that encourage certain behaviours in the participant, leading to a fulfilment of the investigator’s expectations. Such cues act as an EV. e.g. leading questions.
What are participant variables?
The differing individual characteristics that may impact how an individual responds in an experiment e.g. age, gender etc.
Controlled in repeated measures design as same participant used in both conditions.
what is a field experiment?
a field experiment takes place in the real world rather than a controlled environment.
IV is manipulated by researcher.
weakness of field experiment
less control over extraneous variable that might bias the results. makes it difficult to replicate
strength of field experiment
high ecological validity as more likely to reflect real life.
less likelihood of demand characteristics as participants don’t know they are being studied, so don’t change behaviour for experiment.