Experimental Methods Flashcards
what is a laboratory experiment?
- highly controlled environment
- researcher deliberately manipulates the independent variable to investigate the effect on the dependent variable
what is the environment like in a lab experiment?
- highly controlled environment
- artificial environment
within a lab experiment is:
- there random allocation of groups?
- the researcher able to manipulate the IV?
- there control over variables?
- yes
- yes
- yes
why is high internal validity a strength in a lab experiment?
- high control over the environment
- able to reduce the risk of extraneous variables
why is replication a strength in a lab experiment?
enables the research to be repeated to explore the reliability of the findings
why are casual effects a strength in a lab experiment?
due to the high controlled environment, able to establish whether one variable actually causes an effect on another variable
what are the strengths of a lab experiment?
- high internal validity
- replication
- casual effects
how does a lab experiment lack ecological validity?
the environment the research is investigating is artificial, findings cannot be generalised for real-life behaviour
why is demand characteristics a weakness within a lab experiment?
participants are aware that they are being researched, may change their normal behaviour for the experiment
why is deception a weakness within a lab experiment?
participants are not typically aware they are being researched/ are often ‘deceived’ about the aims of the research until the end of the study
what are the weaknesses of a lab experiment?
- lacks ecological validity
- demand characteristics
- deception
what is an example of a lab experiment?
peterson and peterson STM study
what is a field experiment?
typically conducted in a participants natural/ ordinary environment
what happens to the independent variable within a field experiment?
directly manipulated by researcher
are the participants aware they are participating in a field experiment?
no - this enables their behaviour to be seen as more natural
why can the participants being unaware of their participation in a field experiment be a problem?
may be difficult to control extraneous and confounding environment
why is lack of demand characteristics a strength for a field experiment?
participants are not likely to know they are being researched so aren’t likely to guess meaning of the research - natural behaviour
why is ecological validity a strength for a field experiment?
more natural environments than lab experiment, more likely to reflect real life environments
why are casual relationships a strength within a field experiment?
able to manipulate the independent variable and record the dependent variable to identify cause and effect relationships
what are the strengths of a field experiment?
- less demand characteristics
- ecological validity
- casual relationships
why is less control a weakness for field experiments?
less control over extraneous variables which may affect the results of the research
why are ethical issues a weakness for field experiments?
is participants are not aware they are being researched it may be difficult to debrief them - may cause participants distress
what are the weaknesses of field experiments?
- less control over extraneous variables
- ethical issues
what is an example of a field experiment?
teacher deliberately collapses in canteen - investigates students responses
what is a natural experiment?
independent variable is not directly manipulated by researcher, but researcher takes advantage of naturally occurring independent variable
when are natural experiments typically used?
where independent variable cannot be directly manipulated due to ethical/ practical reasons
- DV may be testes in a lab
can participants be randomly assigned to conditions in a field experiment?
no - and there is no direct manipulation of independent variable
within a field experiment, can:
- researcher manipulate IV?
- random allocation of groups occur?
- control over variables?
- no
- no
- no
why is a field experiment ethical/ why is it a strength?
some variables would not be possible to directly manipulate unless they were naturally occurring
why is demand characteristics a strength for a natural experiment?
participants are not aware they are in a research study and are unlikely to behave differently
why is high ecological validity a strength for a natural experiment?
less artificial than laboratory experiment as consists of naturally occurring variables so the findings can be generalised into different settings
why is ‘no cause and effect’ relationship a weakness for a natural experiment?
not able to manipulate the independent variable and other variables could influence the findings, meaning casual relationships can be established indefinitely
why is deception (ethical issues) a weakness for a natural experiment?
often used and no consent can be made
what are the strengths for natural experiments?
- ethical
- demand characteristics
- high ecological validity
what are the weaknesses for natural experiments?
- no cause and effect relationship
- deception (ethical issue)
- confidentiality
why is confidentiality a weakness for a natural experiment?
can lead to the participants being identifiable
what is example of a natural experiment?
the effect of COVID-19 impacting students level of support
what is a quasi experiment?
an ‘almost experiment’
why is a quasi experiment an ‘almost experiment’?
because the independent variable is not something that ‘varies’ but instead something that exists
why does the researcher use random allocation of conditions in a quasi experiment?
because the IV is a feature of the participants e.g. gender, age, personality etc.
within a quasi experiment, can:
- researcher manipulate IV?
- random allocation of groups occur?
- control over variables?
- no
- no
- no
why is high ecological validity a strength for a quasi experiment?
less artificial than laboratory experiment as consists of naturally occurring variables so the findings can be generalised into different settings
why is ‘no cause and effect relationship’ a weakness for for a quasi?
- not able to manipulate the IV
- other variables could influence findings
why is random allocation a weakness for quasi?
there may be other variables that change with the IV that were not controlled
- lack of availability to use random allocations suggest that the research may be at risk of uncontrolled confounding variables
what is a strength of quasi experiment?
high ecological validity
what are weaknesses of quasi experiment?
- no cause and effect relationship
- random allocation
what is ecological validity?
a measure of how test performance predicts behaviour in real world settings
