lesson 12 - practical investigation

Question 1

Aim

Answer 1

A laboratory experiment investigating differences in the recall accuracy of a boat accident (video) when using a Cognitive Interview compared to a Standard Interview.

Question 2

IV and DV

Answer 2

IV: Cognitive Interview Questions vs Standard Interview Questions

DV: Number of the 10 key events from a boat crash accident

Question 3

Hypothesis

Answer 3

Null Hypothesis:
no significant difference in the number of the 10 key events of a boat crash accident between whether the witnesses were interviewed using either the Cognitive or Standard Interview.

One-tailed (directional):
CI will lead to a higher number of the 10 key events of a boat crash accident recalled than when a Standard Interview is used.

Two-tailed (non-directional):
significant difference in the number of the 10 key events of a boat crash accident between whether the witnesses were interviewed using either the Cognitive and Standard Interview.

Question 4

Confounding/extraneous variables

Answer 4

• Time (30 mins)
• time of day (form time)
• age 12 years (all year 7)
• standardised script, structured interviews

Question 5

Experimental design, experimental methodology, sampling technique

Answer 5

• Independent groups
• Laboratory (classroom)
• Opportunity (form time 1.30pm, year 7 form class)

Question 6

Procedure:

Answer 6

• 20 students were split into 2 groups: 10 Cognitive, 10 Standard Interview.
• Pps shown video clip of a boat accident involving 4 boats (2 minutes)
• Standardised script read aloud, to inform students of true aim, right to withdraw and a promise to debrief via email the results after data collection.
• Students were asked 4 questions via a structured interview. (4 CI questions or 4 SI questions). The PPs responses were audio recorded and later transcribed

Content analysis was conducted, the frequency of whether they remember the 10 key events from the boat accident E.g. 1. When the dog jumped off the red boat, 2. When the boom of the big sailboat hit the influencer riding a jet ski etc…

Question 7

Results

Answer 7

Descriptive results:
Cognitive Interview: 7.3 (mean)
Standard Interview: 5.6 (mean)

Cognitive Interview: 2.1 (Standard deviation)
Standard Interview: 1.8 (Standard deviation)

Inferential statistics:
The Mann Whitney U test of difference showed Calculated value U (11.5) was less than the Critical value (23) @p=0.05 and Na 10, Nb 10.

Question 8

Conclusions

Answer 8

There is a significant difference in the number of the 10 key events of a boat crash accident between whether the witnesses were interviewed using either the Cognitive or Standard Interview.

Question 9

Improvements

Answer 9

A02 - The opportunity sample involved a year 7 form class age 12 in Dubai college
A03 -I would take into account different age groups and so range from 12-year-old to 40-year-old who will have different past experiences and thoughts about boats and so their schema may change how aware they are of the 10 key factors. This will increase the representativeness of the conclusion as it can be more generalisable to more age groups.

A02 - The results from interviews of how many of 10 key events recalled from a boat accident were audio recorded and later transcribed
A03 - I would include more than one psychologist analyze the results from the study on the different types of interviews which would increase inter-rater reliability of conclusions.

A02 - The study used independent groups experimental design and split a year 7 form of 20 into 2 groups of 10.
A03 - I would use matched pairs designs such as pairing up individuals on their prior boat knowledge to remove any individual differences. This would increase validity of the study as participant variables are kept to a minimum.

Question 10

BPS ethics

Answer 10

A02 - There was a standardized script read aloud involving the true aim to investigate differences in the recall accuracy of a boat accident (video) when using a Cognitive Interview compared to a Standard Interview, and a promise debrief via email after results were gathered
A03 - This follows te BPS guidelines of no deception as the year 7’s were told the true aim of the experiment immediately after the study to protect them from psychological harm.

A02 - Participants were given the right to withdraw throughout the experiment lasting 30 minutes through form time
A03 - This shows the participants had the right to withdraw themselves and their results of the cognitive or standard interviews at any moment if they felt uncomfortable, following the BPS guidelines.

A02 - Participants were shown a video clip of a boat accident involving 4 boats (2 minutes)
A03 - This meant participants were kept from any emotional response and psychological harm as it was just a video shown to all.