Research Methods Flashcards
(45 cards)
What is an aim?
A precise statement of why a study is taking place. It should include:
- what is being studied
- what the study is trying to achieve
What are the different types of hypotheses? Give Examples
Directional — alcohol will increase reaction time
Non-directional — alcohol will affect reaction time
Null — alcohol will have no affect in reaction time, any difference will be due to chance
What is the independent variable?
The variable that is changed
What is the dependant variable
The thing that changes as a result of the IV
What is an extraneous variable?
Variables (other than the IV) that can have an effect on the DV if not controlled. They do not vary systematically with the IV.
What are the different types of extraneous variables?
Participant variables and situational variables
What is a participant variable?
Individual differences that can include things like
Age
IQ
Fitness
Social class
What are demand characteristics?
The cues in an experiment which convey the aim of the study to the participant.
What is participant reactivity?
The way in which participants react to demand characteristics
Can include please you or screw you effect
How do you control participant variables?
Single blind
What is a situational variable?
Outside influences thigh may have an effect on the experiment such as time of day, weather, noise levels, type of room the experiment takes place in etc.
How do you control situational variables?
Standardisation - making sure RP’s are tested under exactly the same conditions
Randomisation - order of tasks or presentation of data is decided by the toss of a coin (controls order effects)
Counterbalancing - changers order of tasks in an experiment to avoid order effects
What is the investigator effect?
If the researcher changes in any way in the experiment (the way they look, behave or speak to the RP’s) this may effect the results.
How do you control the investigator effect?
Double blind
What is the independent measures design?
Involves using different participants in each condition
What is the repeated measures design?
Where one group of participants takes part in both conditions of the experiment.
What is the matched pairs design?
Uses different but similar RP’s. The RP’s are matched up based on similar characteristics and then one of each pair is put into different conditions
Identify two strengths and two weaknesses of independent groups design
+ no order effects
+ demand characteristics are less likely to affect the results
- individual differences (participant variables)
- less economical as twice as many participants are needed
Identify two strengths and two weaknesses of repeated measures design
+ no participant variables
+ fewer RP’s needed than in independent measures
- results can be affected by order effects (counterbalancing can reduce this)
- demand characteristics can affect the validity
Identify three strengths and two weaknesses of matched pairs design
\+ no order effects \+ reduced individual differences \+ less demand characteristics - need lots of RP's - some are wasted - hard to match participants exactly
What are the 4 different types of experiments?
- Lab
- Field
- Natural
- Quasi
Describe and evaluate the use of lab experiments
Experiment taking place in a highly controlled environment. IV is manipulated and DV is recorded.
+ highly controlled
+ can establish cause and effect
+ can be replicated
+ very scientific equipment = accurate measurements can be made
- lacks generalisability
- demand characteristics can influence behaviour
- lacks Mundane realism
Describe and evaluate the use of field experiments
Field experiments take place in a natural environment
+ holds mundane realism
+ high external validity
- lots of extraneous variables that are hard to control
- hard to replicate
- ethical issues (cannot gain informed consent without giving away too much information)
Describe and evaluate the use of natural experiments
In these experiments there is no manipulation of the IV as it is naturally occurring. The researcher just records the DV (e.g. The effect of a tsunami on future mental illness)
+ high ecological validity
+ no demand characteristics - RP’s do not know they are being watched
- extraneous variables are hard to control
- sample bias as the researcher cannot control who is in the sample. This may make results unable to be generalised