METHOD
Design
The investigation was by the means of an experiment using the within groups design design. In this design some participants undergo condition 1 and the rest undergo condition 2
The independent variables were the 2 conditions. The first condition was the ‘bumped’ condition and the second was the ‘smashed’ condition.
The dependent variable was the blood alcohol content.
Subjects
An opportunity sample was taken from the undergraduate student population at De Montfort University. This sample consisted of 30 males and 30 females between the age group of 18-23
Apparatus & Material
The materials were 2 vignettes as shown in Appendix 1, 2. There was a section for them to write their age, sex, participant code and their responses. 30 vignettes had the first condition i.e. the word ‘bumped’ and 30 had the second condition i.e. the word ‘smashed’. SPSS was used to analyse the data.
Procedure
Each participant was given a copy of the vignette of one of the 2 conditions. The participant had to give their age, sex, participant code and the response. The participant code was taken instead of the name to maintain the anonymity. (as shown in appendix c). Each participant read a passage which described a drinking and driving accident as shown in Appendix A, B. The participants were asked to answer the question which asked them to give an estimate of the blood alcohol content of the person in the accident. The only difference was that in condition one the word used in the passage and question was ‘bumped’ and in condition 2 it was ‘smashed’. It was made sure that there were equal numbers of male and female participants. From the 30 male 15 underwent condition 1 and 15 condition 2. Similar was the case with the females.
RESULTS
The mean no. of digits typed in the bumped condition was 138.33 (sd=45.02), whereas the mean no. of digits types in the smashed condition was 195.03 (sd=61.78). This difference was found to be significant using an independent samples t –test , t(58)= 4.06, p<0.001
DISCUSSION
The results of this experiment support the experimental hypothesis. They signify that the construction of a question systematically affect the answer of the witness. Levene’s test for Equality of Variances (as shown in appendix D) indicated that the likelihood of the population variances being equal in the case of the ‘smashed’ and the ‘bumped’ condition scores is 0.161. As this is more than 0.05 there is no significant difference in the variances of the two conditions, and therefore it can be assumed that they are equal. An independent samples t-test was carried out and it indicated that the results are significant i.e. the mean score in the ‘smashed’ condition is significantly higher than the ‘bumped’ condition.
It can be seen that when participants were asked to respond to the question they decided to take a higher figure in the ‘smashed’ condition since the impact of the word is much stronger.
There were some extraneous variable which might have affected the results. Since all participants did not simultaneously carry out the task there can be a difference in the results e.g. capabilities of participants may vary with the time of day due to different routines. In a replication of this study tasks should be carried out simultaneously. In the vignette given to the participants 3 figures were already given to explain the question. Participants could have replied one of these figures to finish the task faster. Most participants would have given a multiple of 10 since it strikes faster to the mind and hence would not have given a sincere thought to the question, causing a inaccuracy in responses.
REFERENCES
Baddley,A. (1993). Your Memory: A User’s Guide, UK: Penguin Books.
Eysenck,M.,Keane,M. (2001) Cognitive Psychology: A Student’s Handbook, UK:Psychology Press.
Loftus,E. (1974) Reconstruction of Automobile destruction: An Example of the Interaction Between Language and Memory. Journal of Verbal Learning and Verbal Behaviour 13, 585-589.
APPENDICES
Appendix A – ‘smashed’ condition
Appendix B – ‘bumped’ condition
Appendix C – ethics form
Appendix D – Results
APPENDIX A – ‘BUMPED’ CONDITION
THANK YOU FOR TAKING PART IN THIS STUDY.
BEFORE PROCEEDING, PLEASE INDICATE YOUR SEX AND AGE IN THE AREAS PROVIDED, AND THEN CHECK THAT THE BOX LABELLED ‘PARTICIPANT CODE’ IS COMPLETED.
SEX: MALE/FEMALE (Please circle one) AGE:
PARTICIPANT CODE:
_______________________________________________________________
Please read the following short vignette, and then answer the question printed below it.
John Adams left his friend’s house at 2.20am. Although he had been drinking, John decided to drive home because he had been unable to get a taxi. On his way home, John took a short cut. While he was travelling at 38 miles per hour, he lost control of the car and bumped into a garden wall. The police arrived shortly afterwards in response to a call from the house owner, and breathalysed John.
Question
Please estimate John’s blood alcohol content relative to the British legal limit when his car bumped into the wall (e.g. 200% = twice the limit, 100% = on the limit, 50% = half the limit). You can give any number, and this should be entered into the box below:
APPENDIX B – ‘SMASHED’ CONDITION
THANK YOU FOR TAKING PART IN THIS STUDY.
BEFORE PROCEEDING, PLEASE INDICATE YOUR SEX AND AGE IN THE AREAS PROVIDED, AND THEN CHECK THAT THE BOX LABELLED ‘PARTICIPANT CODE’ IS COMPLETED.
SEX: MALE/FEMALE (Please circle one) AGE:
PARTICIPANT CODE:
_______________________________________________________________
Please read the following short vignette, and then answer the question printed below it.
John Adams left his friend’s house at 2.20am. Although he had been drinking, John decided to drive home because he had been unable to get a taxi. On his way home, John took a short cut. While he was travelling at 38 miles per hour, he lost control of the car and smashed into a garden wall. The police arrived shortly afterwards in response to a call from the house owner, and breathalysed John.
Question
Please estimate John’s blood alcohol content relative to the British legal limit when his car smashed into the wall (e.g. 200% = twice the limit, 100% = on the limit, 50% = half the limit). You can give any number, and this should be entered into the box below:
APPENDIX C –ETHICS FORM
APPENDIX D – RESULT
Means
Case Processing Summary
Report
response