Loftus et al

Loftus et al

Aim: To provide support for the 'weapon focus' effect when witnessing a crime.
Pps: 26 University of Washington students aged 18-31. They received an incentive for participating.
Procedure:
1. 2 sets of slides were shown. The 18 slides in each series showed people queuing in a 'Taco Time' restaurant.
2. In the control group person B (the person 2nd in the line) hands the cashier a cheque.
3. In the experimental group person B pulls a gun (the independent variable).
4. All the other slides in both series were identical and shown for 1.5 seconds.
5. The pps were told it was a study of proactive interference.
6. The dependent variable was measured by a 20-item multiple-choice questionnaire.
7. The pps were also given a line up of 12 head-and-shoulder photos in a random order and were asked to rate how confident they are of their identification on a scale of 1-6 (1=guess 6=very sure).
Results:
1. Answers to the questionnaire about the slide show showed no significant difference between the two conditions..
2. Chance performance on the photo line-up was calculated to be 8.5%.
3. In the control condition 38.9% chose the correct person B against 11.1% in the weapon condition.
  1. The result is significant.
4. There was no difference in the confidence level of either group.
5. Eye fixation data showed 3.72 was the average number of eye fixations on the gun in comparison to 2.44 on the cheque.
  1. This is also significant.

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	Created by leonie1997 almost 11 years ago