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Research Methods- laboratory and field experiments - Coggle Diagram
Research Methods- laboratory and field experiments
field experiments
Benefits to EWT research
Provides some reliability within EWT studies because the researcher can control the IV e.g. In Yuille and Cutshall’s study they introduced…
The IV can be introduced by another researcher in another study, showing replicability.
Provides studies high ecological validity within EWT studies because the natural elements of the crime scene have been experienced by the witnesses e.g. In Yuille and Cutshall’s study…
Provides studies of EWT with low demand characteristics because participants are in their natural surroundings and are less likely to be thinking about what the researchers are studying.
Problems to EWT research
Creates some issues with reliability as the researcher does not have control over the extraneous variables in the natural environment that may influence the witness e.g. In Yuille and Cutshall study..
This means the study can not be replicated by other researchers.
Creates problems of ethical issues within EWT studies because participants experience some natural elements of crime and need to recall this event e.g. In Yuille and Cutshall’s study..
How are they used in field experiments within EW research
The researcher controls/manipulates a factor that might influence a witness (artificial task) e.g. Yuille and Cutshall introduced 2 leading questions about a busted headlight and colour of a car panel.
The researcher records the effect of the IV on the DV testimony of the witness e.g. Yuille and Cutshall recorded the effect of the 2 leading questions on the witnesses ability to recall the details of crime (whether they saw a busted headline/yellow panel).
The witnesses are in their natural environment for some aspects of the study e.g. witnesses in Yuille and Cutshall’s experiment were in their everyday environment when they were asked to recall the details of the robbery.
Witnesses may not be given the opportunity to give consent to take part in the research e.g. some studies have taken place in a lecture room where students were unaware the crime was controlled by the researcher.
laboratory experiments
how are they used in laboratory experiments within EW research
The researcher controls/manipulates a factor that might influence a witness (artificial task) e.g. Loftus introduced a leading question with the verbs smashed, hit, collided, bumped or contacted.
The researcher records the effect of the IV on the DV - testimony of the witness e.g. Loftus recorded the effect of a leading question on the participants estimated speed of how fast the cars were travelling
The researcher may use a control group to compare the accuracy of testimonies given by witnesses who have experienced the IV with witnesses who haven’t e.g. In experiment 2 Loftus compared the testimonies of witnesses who have experienced the leading question/weapon focus with testimonies of witnesses who haven’t.
The witnesses are in an artificial environment such as a classroom/conference room this e.g, in Loftus’ study participants were in a university lecture room, watching a film of a car crash.
Witnesses give their consent to take part in the research (usually general consent) e.g. university students consented to take part in Loftus’ study.
Problems to EWT research
Lack of ecological validity: Video clips of crimes lack realism as they do not involve the same degree of emotion. Giving a testimony to a researcher also lacks realism as real witnesses give testimonies to the police/courts and are aware of the consequence of their answers.
Lack of ecological validity: the artificial environment of the crime does not include practical factors experienced by real witnesses such as distraction and physical obstructions.
Demand Characteristics: Pp were undergraduate psychology students, aware they were taking part in a study - may be more willing to co-operate with the task of watching the film and answering questions than a real witness (not all real witnesses are helpful/willing to share memories of event).
Benefits to EWT research
Reliable because….control over IV and DV e.g. leading questions and estimate speed. This means that other researchers can check the consistency of results and make conclusions about the accuracy of EWT.
Ethical because general consent usually gained
Ethical because knowing the event isn’t real – it is less distressing for the Pp to watch a film clip of a car accident than if they believe it is a real incident.
Good internal validity – control group used in experiment 2 so can compare accuracy of EWT between experimental group with control group to check effect of the IV (leading Q/weapon focus)