Making A Case

Question 1

1.2 Loftus et al- factors about ‘weapon focus’: Aim:

Answer 1

To provide support for the ‘weapon focus’ effect when witnessing a crime

(Weapon focus refers to the concentration of a crime witness’s attention on a weapon and the resultant difficulty in remembering other details of the scene)

Question 2

1.2 Loftus et al- factors about ‘weapon focus’: methodology

Answer 2

A Lab experiment

Question 3

1.2 Loftus et al- factors about ‘weapon focus’: participants

Answer 3

36 students at the university of Washington, aged 18-31. Half were recruited through an advertisement and were paid $3.50 for their participation, the remainder participated in exchange for extra credit in their psychology classes

Question 4

1.2 Loftus et al- factors about ‘weapon focus’: procedure

Answer 4

The 18 slides in each series showed people queuing in a Taco Time restaurant.
in the control group, a person hands cashier a cheque
Experimental group= pulls a gun

All the other slides in both series were identical and shown for 1.5 seconds.

Participants were told that the study was proactive interference (when something that you learned earlier interferes with your memory of the present)
The DV was measured by a 20- item multiple choice questionnaire. Participants were also given a line up of 12 head and shoulder photos in a random sequence and were asked to rate how confident they were of their identification out of 6.

Question 5

1.2 Loftus et al- factors about ‘weapon focus’: results

Answer 5

Answers to questionnaire showed no significant difference. 38.9% correct person in cheque condition
11.1% in gun condition correct
No difference in confidence
Eye fixation data showed an average of 3.72 on gun and 2.44 in cheque.

Second experiment same procedure, 80 psychology students, consistent findings.

Question 6

1.1- Bruce et al- the importance of external and internal features in face recognition: Aim

Answer 6

Photo array task to compare the quality of external and internal composite features. This was intended to be similar to a police line-up identification process.

Question 7

1.1- Bruce et al- the importance of external and internal features in face recognition: experiment 1

Answer 7

P’s: 30 staff and students from Stirling University were paid £2 to sort the composites (15 m 15 f aged 18-60)
Lab exp. independent
Stimuli target photographs of 10 celebs and 40 composite images produced by either: E-fit, Pro-fit, sketch and Evo-fit, three sets of composites were used: complete set of features, internal features and external features
Randomly assigned to each group.
Results: 33% correct for external and 19.5% correct for internal. Familiarity was not a significant factor

Question 8

1.1- Bruce et al- the importance of external and internal features in face recognition: experiment 2

Answer 8

P’s: 48 undergraduates at Stirling university. (21 m and 27 female) all volunteers aged between 18-31
Lab exp. independent. Used a photo array of photo line-up with distractor faces (foils). Allocated randomly to one of 4 groups: easy faces, easy foils, internal hard, external hard.
Results: 42% recognition of external composites and 28% of internal composites.

Question 9

1.1- Bruce et al- the importance of external and internal features in face recognition: experiment 3

Answer 9

30f and 24m (54) who were unfamiliar with faced were asked to match composites external and internal

26 separate participants who were likely to know the targets were asked to name them, only full composites were used:

Findings: sorting was 58% accurate but familiarly made no difference.

Question 10

1.3 Fisher et al- field test of the cognitive interview: AIM

Answer 10

To test the cognitive interview in the field

Question 11

1.3 Fisher et al- field test of the cognitive interview: methodology

Answer 11

Field experiment with actual interviews of real witnesses by serving police detectives

Question 12

1.3 Fisher et al- field test of the cognitive interview: participants

Answer 12

16 detectives from the robbery division of Dade county, Florida. All had a minimum of 5 years experience

Question 13

1.3 Fisher et al- field test of the cognitive interview: procedure

Answer 13

Phase 1:
Detectives recorded standard interviews for 4 months totalling in 88 interviews

Phase 2:
Training was over four 60 minute sessions. Seven detectives complete the programme. Over the next 7 months more interviews were recorded by the two groups and analysed by uni of California (blind conditions)

Question 14

1.3 Fisher et al- field test of the cognitive interview: results

Answer 14

Trained detectives elicited 47% more info than before, 63% more info then untrained detectives. 85% of all statements correct in all conditions,

Thus strong support of effectiveness of the cognitive interview