Loftus and Palmer

Loftus and Palmer

1. Aim

   • Information supplied before and after the event.

2. Methodology

   • Laboratory
   • Independent measures design
   • Snapshot
   • Iv: verb in the question
   • Dv: speed estimate or broken glass

3. Experiment 1

   • Conditions
     • Smashed
     • Hit
     • Collided
     • Bumped
     • Contacted
   • Sample Size
     • 45 students from Washington University
       • 9 in each of the 5 conditions
   • Procedure
     • 7 clips of road traffic accidents
       • Describe what they had seen
     • Questionnaire
       • Critical question
         • 'How fast were the vehicles travelling when they (condition) into each other?'

4. Experiment 2

   • Conditions
     • Smashed
     • Hit
     • Not asked (control)
   • Sample size
     • 150 students
       • 50 in each condition
   • Procedure
     • Shown the same film clips as Experiment 1
       • Given the questionnaire with the relevant critical question
     • A week later...
       • Without seeing the video again
       • Asked whether or not they saw broken glass
       • There was none

5. Data

   • Quantative

6. Findings

   • Experiment 1
     • Smashed
       • 40.8
     • Collided
       • 39.3
     • Bumped
       • 38.1
     • Hit
       • 34.0
     • Contacted
       • 31.8
     • Smashed was the highest
     • Contacted was the lowest
   • Experiment 2
     • Smashed
       • Yes
         • 16
       • No
         • 34
     • Hit
       • Yes
         • 7
       • No
         • 43
     • Control
       • Yes
         • 6
       • No
         • 44
     • In the smashed condition, people were more likely to say yes

7. Conclusion

   • Could be due to a distortion
     • Verbal label fitted with the schema of a more severe crash
       • In which there may or may not be broken glass
   • Response bias
     • Demand characteristics
       • As a university student might try to impress their lecturer
   • Two types of information integrate into one memory
     • Information received as a witness
     • Information supplied later
     • Hard to distinguish between the two sources
       • Only one memory

8. Evaluation

   • Ethics
     • No problem
   • Ecological Validity
     • Did not undergo any of the emotional trauma
       • No longer true to life
   • Validity
     • It may be testing response bias
   • Reliablity
     • Lots of controls
       • Repeatable
       • Consistant
   • Applicability
     • Don't use leading questions in court
   • Stengths
     • A laboratory experiment
       • High controls
       • Reliable
     • Independent measures design
       • only experience one condition
         • Wont be affected by order effects
   • Weakness
     • Participant did not feel the stress
       • Memory may be affected by this
         • Low validity
     • Demand characteristics