Loftus and palmer (cognitive) Flashcards
What effects eye witness testimony ?
Leading questions
What was the aim of the study ?
They aimed to investigate the effects of leading questions on the accuracy of eyewitness testimony
What is the IV ?
The verb used e.g
Smashed Collided Bumped Hit Contacted
What is the DV ?
The participants estimate of the speed in MPH
What was the sample ?
45 students from Washington university
What experimental design was used ?
Independent measures design
What were the apparatus ?
7 film segments of car crashes that lasted between 5-30 seconds from the Evergeen safety council of the Seattle police department
Each p’s was given a questionaire about the film clips
They were asked to give an account of what they hd seen
P’s were given a set of 10 questions about the accident including how fast they thought it was going with the verb of choice
What was the procedure?
P’s shown each film clip which was immediately followed by the questionaire
The critical question about the speed differed between the conditions as the verb changed
The films were presented in different orders to p’s
Findings - Actual speed of crash vs estimated speed
Film 1 = actual speed - 20 MPH, mean speed estimate - 37.7 MPH
Film 2 = actual speed - 30 MPH, mean speed estimate - 36.2 MPH
Film 3 = actual speed - 40 MPH , mean speed estimate - 39.7 MPH
Film 4 = actual speed - 40 MPH, mean speed estimate - 36.1 MPH
P’s were not accurate when estimating the speed of a vehicle
Findings - verb vs mean speed estimate
Smashed = 40.8 Collided = 39.3 Bumped = 38.1 Hit = 34.0 Contacted = 31.8
Findings ?
Of the 5 verbs smashed had the highest average speed estimate of 40.8 MPH
Contacted had the lowest average speed estimate of 31.8 MPH
The differences in speed estimates between the conditions was found to be statistically significant
Explaining the findings ?
Response bias - consciously changes response due to verb as they think thats what the researchers want
Distortion - the verb caused a change in the p’s memory of the event
