Research methods
Students should demonstrate knowledge and understanding of the following
research methods, be familiar with their use and be aware of their strengths
and limitations:
- Experimental method. Types of experiment, laboratory and field
experiments; natural and quasi-experiments.
- Observational techniques. Types of observation: naturalistic and
controlled observation; covert and overt observation; participant and
non-participant observation.
- Self-report techniques. Questionnaires: interviews, structured and
unstructured.
- Correlations. Analysis of the relationship between co-variables. The
difference between correlations and experiments.
Types of Experiments
Laboratory Experiments
- Conducted in a controlled environment (doesn’t have to be in a lab)
- Researcher manipulates the IV to see what effect it has on the DV.
Strict control over EVs
- Participants are aware they are taking part in a study although they
may not know the true aims
- Strengths:
- It is well controlled so EVs are minimised thus there is higher
internal validity
- It also establishes the ‘cause & effect’
- It can also be easily replicated because of high levels of control,
demonstrating external validity (as you can check if results are
valid)
- Weaknesses:
- Artificial, a contrived situation, participants may not behave as
they would in real life, leading to low internal validity.
- Participants may know they are being studied so demand
characteristics operate.
- Material may lack mundane realism as it is ‘artificial’
Field Experiments
, - Conducted in a more natural environment, anywhere outside a lab
where investigated behaviour could naturally occur
- Researcher manipulates the IV to see what effect it has on the DV
- IV is deliberately manipulated by the researcher but participants not
always aware they are participating in an experiment
- Strengths:
- Less artificial so usually has higher mundane realism and higher
ecological validity.
- Participants are usually aware they are being studied so there is
a reduction in demand characteristics, more authentic/valid
behaviour is produced
- Weaknesses:
- Less control of EVs which reduces internal validity as ‘cause and
effect’ is more difficult to establish
- More time consuming so it is more expensive.
- There can be and invasion of privacy/ ethical issues if
participants are unaware, they are being studied due to lack of
consent
Natural Experiments
- Researcher takes advantage of pre-existing IV, this is a natural
experiment because the variable would have changed even if the
experimenter wasn’t interested
- The IV is natural not necessarily the setting – participants may be tested
in a laboratory
- Strengths:
- Allows research where IV can’t be manipulated for ethical or
practical reasons
- Enables psychologists to study ‘real’ problems such as the effect
of disaster on health (increased mundane realism and ecological
validity
- Weaknesses:
- Can’t demonstrate casual relationships because IV is not directly
manipulated.
- Random allocation is not possible so there may be EVs that can’t
be controlled which is a threat to internal validity, as it reduces
the clarity of the effect of the IV on the DV. This makes the
research socially sensitive
- Naturally occurring events may happen rarely, reducing
opportunities for research. Can only be used where conditions
vary naturally
Quasi Experiments
Students should demonstrate knowledge and understanding of the following
research methods, be familiar with their use and be aware of their strengths
and limitations:
- Experimental method. Types of experiment, laboratory and field
experiments; natural and quasi-experiments.
- Observational techniques. Types of observation: naturalistic and
controlled observation; covert and overt observation; participant and
non-participant observation.
- Self-report techniques. Questionnaires: interviews, structured and
unstructured.
- Correlations. Analysis of the relationship between co-variables. The
difference between correlations and experiments.
Types of Experiments
Laboratory Experiments
- Conducted in a controlled environment (doesn’t have to be in a lab)
- Researcher manipulates the IV to see what effect it has on the DV.
Strict control over EVs
- Participants are aware they are taking part in a study although they
may not know the true aims
- Strengths:
- It is well controlled so EVs are minimised thus there is higher
internal validity
- It also establishes the ‘cause & effect’
- It can also be easily replicated because of high levels of control,
demonstrating external validity (as you can check if results are
valid)
- Weaknesses:
- Artificial, a contrived situation, participants may not behave as
they would in real life, leading to low internal validity.
- Participants may know they are being studied so demand
characteristics operate.
- Material may lack mundane realism as it is ‘artificial’
Field Experiments
, - Conducted in a more natural environment, anywhere outside a lab
where investigated behaviour could naturally occur
- Researcher manipulates the IV to see what effect it has on the DV
- IV is deliberately manipulated by the researcher but participants not
always aware they are participating in an experiment
- Strengths:
- Less artificial so usually has higher mundane realism and higher
ecological validity.
- Participants are usually aware they are being studied so there is
a reduction in demand characteristics, more authentic/valid
behaviour is produced
- Weaknesses:
- Less control of EVs which reduces internal validity as ‘cause and
effect’ is more difficult to establish
- More time consuming so it is more expensive.
- There can be and invasion of privacy/ ethical issues if
participants are unaware, they are being studied due to lack of
consent
Natural Experiments
- Researcher takes advantage of pre-existing IV, this is a natural
experiment because the variable would have changed even if the
experimenter wasn’t interested
- The IV is natural not necessarily the setting – participants may be tested
in a laboratory
- Strengths:
- Allows research where IV can’t be manipulated for ethical or
practical reasons
- Enables psychologists to study ‘real’ problems such as the effect
of disaster on health (increased mundane realism and ecological
validity
- Weaknesses:
- Can’t demonstrate casual relationships because IV is not directly
manipulated.
- Random allocation is not possible so there may be EVs that can’t
be controlled which is a threat to internal validity, as it reduces
the clarity of the effect of the IV on the DV. This makes the
research socially sensitive
- Naturally occurring events may happen rarely, reducing
opportunities for research. Can only be used where conditions
vary naturally
Quasi Experiments
