Lofus And Palmer Flashcards
What were the aims
To see how phrasing a question differently can influence judgement
Leading questions leading us to the desirable/true answer
What was the method?
Lab experiment
What was the type of data collected
Quantitative - Speeds…mph
- Broken glass…yes/no
What was the level of data collected?
Interval ratio data
Nominal data
What are the factors that affect our memory
Repressed memory
Brain damage
Drugs
Schema
What was the experimental design
Independent measures design - participants will only see one condition
What was the IV?
The verbs in the question:
Hit Smashed Collided Contacted Bumped
What were the 5 verbs used?
Hit Smashed Collided Contacted Bumped
What was the DV?
Their judgement on speed - mph
Broken glass - yes/no
How was the IV manipulated?
The wording of the question:
Hit Smashed Collided Contacted Bumped
How was the DV measure?
The speed in MPH
A simple yes or no
Controls:
Each person saw the same clip
Had the questions asked in the same way
IT WAS STANDARDISED
What was the sample size?
1st - 45 psyc students
2nd - 150 psyc students
Where were the sample from
They were her psychology undergrads from Washington uni
How were they sampled
Opportunity sampling - from her classes
What was procedure for the 1st experiment?
- Participants were shown 7 clips lasting up to 3 seconds
- given a questionnaire after the clips
- 1st half - account of the accident
2nd half - questions relating to it - how fast were the cars going when they —- eachother?
- each person received a different verb in the question of their questionnaire
What was the procedure of the 2nd experiment?
- two part procedure (150 students)
- watch a film + fill in questionnaire - film lasted less than 1 minuet
- a week later fill in a questionnaire without asking about the broken glass
- so subjects (the control) weren’t asked about the speed
Each clip lasted from 5-30 seconds from Seattle police dept
What was the data analysis
Means of speed - chi squared
What were the findings of the 1st experiment?
Smashed - 40.8 Collided - 39.3 Bumped - 38.1 Hit - 34.0 Contacted - 31.8
What were the findings of the 2nd experiment?
- smashed = higher speed - more likely to answer yes to seeing broken glass
- differences between ‘hit’ and the control were too little.
Conclusions
The questions asked can cause a reconstruction in ones memory of the event. The verb used can affect the whir eases account of speed and whether they recall seeing broken glass
Key themes
Memory - info received after the event will effect the memory of the event
Face validity
High - intended to test memory and it did
Construct validity?
High. It’s a test totally on memory and ability to recall information however they didn’t know about leading question
Criterion
The way question are constructed will have an effect in the future. - high.
Interval validity?
High internal validity as in a lab so controlled all extraneous variables
Demand characteristics, her students are trying to please her so will preform better
Population validity?
We can generalise it to her classes but not to old people and those not it education. It’s ethnocentric so only to Americans.
Ecological validity?
Low. In real life more stress and distress involved. In a lab setting so artificial behaviour.
Inter-rater reliability
Simple yes or no answer or speed. No from for discretion
Split half reliability?
The questionnaires in the 2nd study. One done then another the same a week later.
Key theme
The effects of language on memory
