loftus and palmer

Question 1

introduction - post event information and leading questions + what did Marshall find

Answer 1

• post event information is the potential of altering memory of events
• a leading question is a question that prompts/ encourages the answer wanted
• Marshall administered a test to air force personnel of speed estimates which ranged from 10-50 mph when the car was really going 12 mph

Question 2

what was the aim of study?

Answer 2

to investigate the phasing of the question used to elicit speed judgement

Question 3

summarise experiment 1

Answer 3

• 45 students from uni of washington
• 7 films depicting a traffic accident, segments (5-30 sec) from longer driver education films from the evergreen safety council and Seattle police department
• critical question of “about how fast were the cars going when they HIT each other”
• hit, smashed, collided, bumped, contacted
• films presented in different order to each group with the experiment lasting 1hr and 30 mins

Question 4

what were the results for experiment 1?

Answer 4

• mean speed estimates for smashed = 40.5, hit = 34.0
• leading questions had an impact on speed estimates
• 2 possible reasons = 1) response bias factors 2) the question form causes a change in the subjects memory representation of the accident

Question 5

why was experiment 2 conducted?

Answer 5

• to provide additional insights into the origin of the differential speed estimates

Question 6

give a summary of experiment 2

Answer 6

• 150 students who watched a film depicting multiple accidents, lasted less than a minute with the collision being 4 seconds
• received a questionnaire asking them to describe the accident in their own words and then answer a series of questions
• 3 conditions of critical question … smashed, hit and no interrogation
• one week later asked “did you see any broken glass”

Question 7

what were the results for experiment 2?

Answer 7

• mean speed estimates : smashed = 10.46, hit = 8.00
• probability of saying yes to the broken glass question when smashed = 0.32, when hit = 0.14

Question 8

what is an issue with sample size and a counterargument?

Answer 8

• experiment 1 had a small sample size of 45 students so any anomalous results would have a larger impact on the sample
• CA : experiment 2 had a larger sample size of 150 students

Question 9

what is a strength of the study in terms of reliability?

Answer 9

• standardised procedures used e.g. the film lasted for less than 1 minute in experiment 2 and the collision lasted for 4 seconds
• experiment can be repeated for consistency

Question 10

what is an issue with the sample consisting of university students?

Answer 10

• they are all at an age in which they are either new to driving or don’t drive which may affect their ability to make accurate speed estimates, if older people were asked there may have been more accurate estimates

Question 11

applications - what should the police use to question people?

Answer 11

• they could use cognitive interviewing techniques which aims to maximise the accuracy of information recall by having eyewitnesses reinstate the context, report every detail and recall from different perspectives/orders
• geiselman found that the average no. of accurately recalled facts was significantly higher (41.2 compared to 29.4)

Question 12

what extraneous variables were controlled for?

Answer 12

• the short films (5-30 sec in exp 1 and less than 1 min in exp 2) kept ppt. attention and allowed them to witness the crash fully
• prevented reconstruction of memory being based on which bits of the film that the person saw

Question 13

why is the critical question being randomly included amongst other questions within a questionnaire a strength?

Answer 13

• increases the internal validity because it reduces the chance of the ppts guessing the aim of the study and so fewer demand characteristics will be shown
• e.g. “about how fast were the cars going when they HIT each other”

Question 14

what can be said about ecological validity/ task validity?

Answer 14

• low ecological validity as it took place in a labatory environment
• low task validity as watching a film of a crash isn’t the same as seeing one in real life and so may not bring up the same emotions and anxiety which could affect memory

Question 15

what is a strength of the data gathered?

Answer 15

• data gathered was quantitative e.g. speed estimates such as 40.5 in the smashed condition for experiment 1
• objective and not open to bias, can be easily statistically analysed