COGNITIVE: Loftus & Palmer Flashcards
Explain the methodology of loftus and palmer
- experiment
- conducted in a lab
- experiment 1: 45 students, IV: verb used, DV: estimate of speed
- experiment 2: 150 students, IV: verb used, DV: did they see glass
Explain procedure of loftus and palmer
experiment 1
- 7 films shown of a traffic accident, 5-30 seconds long
- participants given questionnaire
—> ‘give an account of what you have just seen’ , then specific Qs then critical Q: ‘how fast were the cars going when they hit each other’
- 9 for each of hit, smashed, bumped, collided, contacted (5 groups total)
- Ps estimates of speed in mph were recorded
- 1.5 hr long experiment
experiment 2
- shown film of multiple vehicle car crash. Less than 1 min, accident last less than 4 sec
- Ps given questionnaire
—> describe accident in own words
—> critical Q ‘how fast were cars going when they __ each other’
- 50x smash, 50x hit, 50 x control
- one week later Ps returned and answered Qs about accident, critical Q ‘did you aww any broken glass?’
- no broken glass in vid but subjects in smashed condition expected to say yes more often.
Explain the findings of experiment 1
- speed estimates for verbs used in experiments:
Smashed: 40.8
Collided: 39.3
Bumped: 38.1
Hit: 34.0
Contacted: 31.8
- also a statistical test showed that the verbs used had a significant effect on speed estimation
Explain the findings of experiment 2
- mean speed estimate for smashed as 10.46mph
- mean peed for hit was 8mph
—> significantly different
Response of yes:
- smashed: 16
- hit: 7
- control: 6
Response of no:
- smashed: 34
- hit: 43
- control: 44
- a statistical test showed the verb used has a significant effect on the probability of saying yes to broken glass
Outline the conclusions of loftus and palmer
- findings suggest that the form of a question can influence a witnesses answer
- two possible conclusions for experiment 1:
1. Response bias factors - different speed estimates occur due to the critical word influencing responses
2. Memory of representation is altered: critical word changes persons memory so that their perception is influenced (ie think it was more serious than it was)
—> suggest Ps remember details that are also not true, as shown by experiment 2 findings - overall conclusion could be that due to findings of experiment 2, it is suggested that the effect of leading questions is due to them actually altering the memory a person has or an event, not response bias
Evaluation, ethics: valid consent
- weakness as was not gained
- Ps were also deceived about the true aim
—> but if they had known it would’ve impacted behaviour and therefore not provided a useful insight into EWT - BPS guideline of respect
Evaluation, ethics: deception justified
- strength
- loftus and palmer emphasised importance of their research as it demonstrated the inaccuracy of EWT (cost vs benefits)
- from the Ps point of view, deception was only mild, and if they had known they true aim it is unlikely they would’ve withdrawn
- BPS guidelines respect
Evaluation, ethics: psychological harm avoided
- strength
- watch clips of accidents
- prevent harm in comparison to if they had been subjected to a real accident which would have been distressing and not helped by debriefing
- BPS guidelines of responsibility
Ethics, evaluation: social implication
- strength
- importance in understanding inaccuracy of EWT
- in courts of law, need to be aware that EWT may have been distorted
- people could become too sceptical of EWT which is not good as it is still valuable info and need to be listened to
- biggest implication of unreliable EWT is risk society faces if real perp remains free
- application
Evaluation, ethics: developments
- strength
- social implication
- improvements and developments such as safeguard which are built into justice system regarding EWT
- interviewing techniques by police have been improved to prevent leading Qs being used
- applicable
methodology and procedure evaluation: control
- strength
- lab experiment - control of variables, findings due to IV not extraneous or confounding variables
- standardised procedures —> repeated for replicability and reliability
—> consistent findings ensure it’s not by chance - internal validity
methodology and procedure evaluation: lab experiment
- weakness
- artificial enviro lead to unnatural behaviour (demand characteristics)
- no motivation to get right or wrong as an experiment, if it were real, might be inclined to get it right bc it’s a crime and people could be injured etc etc
- video clips not real experiment - didn’t witness in person, emotions weren’t involved which would impact memory
- low ecological validity
methodology and procedure evaluation: sample
- weakness
- one area of America
- all American and all college students
—> college students are young, actively studying, good attention to detail and used to recalling things. Compared to old person who hadn’t studied in years, results could differ - can’t generalise
- schemas vary from person to person
- lacks population validity
