Psychology A2

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  • Created by: Lizzie
  • Created on: 03-10-13 17:48

Yuille and Cutshall (1986)

Aim: to investigate the accuracy in recall of eyewitnesses to a real crime, in response to 

leading questions and over time.

Procedure: - five months after the 21 eyewitnesses were asked to take part. 13 said yes.

- aged 15-32 and only three were female, ten were male

- Ppts gave their account and were then questioned (incl. 2 leading questions)

- 'did you see a/the broken headlight/yellow panel?'

- asked to rate the stress they had felt using a tailored seven-point scale

Findings: - misleading questions had little effect on recall, 10 ppts answered q's correctly

85% of central witnesses were accurate, compared with 70% of the peripheral group

- Stress did not affect memory negatively (adrenaline)

Conclusions:eyewitnesses are actually very reliable

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Loftus and Palmer Experiment 1 (1974)

Aim: to see the effect of leading questions of eyewitnesses’ ability to recall information

Procedure:45 student ppts were put into groups and shown short films of car accidents

- after they were given a uestionnaire to fill in

- five different conditions where the critical verb was changed

- 'how fast do you think the cars were travelling when they hit/smashed/collided each other?'

the average estimation was taken for each participant group

Findings:‘smashed’ gave an average estimate of 40.8mph, ‘contacted’ was 31.8mph

- the more “extreme” the verb, the higher the average estimation of the cars’ speeds

Conclusions: - leading q's significantly effect eye witness statements 

- EW's are unreliable

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Loftus and Palmer Experiment 2 (1974)

Procedure: - a sample of 150 student participants were shown a 4 second clip of a car collision

- The ppts were then asked questions about the video

- they were divided into three condition groups. The control group was not asked about speed.

- 'how fast do you think the cars were travelling when they smashed/hit each other?'

- One week later, the participants were given a second questionnaire to fill in

- All groups were asked 'did you see any broken glass?'

Findings: - (broken glass?) when the critical verb was 'smashed' 16 said yes, 34 said no. 'Hit' group, 7 and 43 respectively

Conclusions: - external forces can affect witness recall

- EW's are unreliable

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Yuille and Cutshall (1986) Evaluation

 A field study and so has real life application

+  Scoring procedure meant they gathered quantitative data which is subjective

-  Lacks generalisability as it was a unique incident 

-  A field study and so lacks tight controls, may lack experimental validity

-  Ppts could have had flashbuld memory

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Loftus and Palmer Experiment (1974) Evaluation

+  lab exp. and scientific, manipulated IV therefore can be replicated and tested for reliability

+  gathered quantitative data e.g. the 'yes/no' questions, objective as didn't need to be interpreted

-  lacks validity as ppts may not have been in the same mental conditions and their responses may have been affected

-  lacks population validity as only students were ppts, may not generalise to other groups

-  lab experiment and so lacks real life application as people may not have behaved as they would if they had to be a real life eye witness

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Yarmey (2004)

Aim: to study the reliability of EWT  involving EW recall and photo identification of a target from a photo line-up.

Procedure: - a sample of 590 participants were selected at random by opportunity sampling in public place

- approached by a female target who would ask for directions/help finding a lost piece of jewellery

- Later, the ppt is approached by a researcher and asked to participate in a study on EW recall

16-question recall test (remembering clothing and characteristics)

-  ppt is given a photo line-up, consisting of six photos and asked to identify the target

Findings: - when the target was in the photo line-up, ppts correctly identified her 49% of the time, when she wasn't, 62% said she wasn't there

Conclusions: - about 50% of the time, a witness makes a correct identification when they are in the photo line-up

jurors are likely to overestimate an eyewitness’ ability to recall

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Yarmey (2004) Evaluation

+  the study was carefully controlled as an experiment, and so is replicable so reliability can be tested for

+  high in ecological validity, as it was conducted in the field

+  a large participant sample of both men and women which consisted of a wide range of people from different backgrounds, and so it could be argued that the results are generalisable

-  lacks generalisability to other situations,  target asked for directions/help, there is no evidence from this study to show reliability of EWT for criminal situations

-  the study did not exactly highlight the strengths of eyewitness testimony

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EWT

- The reliability of eyewitness testimony (EWT) is one of the key issues for this application to psychology

- an eyewitness is someone who experiences an incident first hand

- can be affected by leading questions

- used by police to question witnesses/courts as evidence for a case

- example e.g. william dillon whow as released after being falsely accused due to DNA evidence

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Evaluate the reliability of EWT

+  supporting evidence e.g. Y+C (explain...)

+  

+  

-  L+P conclude EWT is not reliable because of leading questions

-  some studies may not apply to EWT as experiments may not concern crime (e.g. Yarmey)

-  

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Rosenthal and Jacobson (1968)

Aim: to investigate  the concept of a self-fulfilling prophecy on the achievement levels of school pupils - could these pupils be made  "more intelligent" by their teachers beh. towards them?

Procedure:teachers were told at the beginning of a school year that one group of children in their class would be about to ‘bloom’, whilst the others were to remain at standard level

– the children were in fact assorted into groups at random

researchers gave the students an IQ test before the study began so teachers believed them

Over the year, those who were set to ‘bloom’ were believed to have received increased attention and opportunities to improve by their teachers as their teachers saw them as bright

Findings:-the 'bright' children had improved their IQ score more than the other pupils

Conclusions: therefore they had evidence of a self-fulfilled prophecy.

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Rosenthal and Jacobson (1968) Evaluation

+  The study was well-controlled, teachers didn’t know the pupils real IQ scores

+  Study can be replicated to test for reliability

+  The study has ecological validity for use in schools, as conducted in a real school setting

-  not applicable to crime as not help in a typical 'criminal' setting

-  unethical, as it is not acceptable to allow some students at school to receive less attention than others, interfering with their education and the teachers were deceived

-  All children from one school, cannot be generalised to other groups

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Jahoda (1954)

Aim: investigating the effects on behaviour from labels

Procedure: - He studied a Ghanaian ethnic group, the Ashanti, noting boys were named according to the day on which they were born

Ashanti's believe ‘Monday’ boys, are quiet and placid, and ‘Wednesday’ boys are aggressive

Findings: - 22% of violent offences were committed by Wednesday boys, only 6.9% by Monday boys

Conclusions:cultural expectations about the boys’ natures and their labels led to differentiated treatment of the boys

- the results are too significant to be left to chance

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Jahoda (1954) Evaluation

+  naturalistic study where the variables were not manipulated, the data came from official court records and were valid

+  results seem too significantly conclusive to be down to some other factor, and it is difficult to find another factor which could have influenced these results so significantly

-  The data cannot be said to be reliable because the study has not been replicated – it is difficult to replicate due to it being a naturalistic study

-  Although it is hard to find another factor which could have led to these findings, it is possible that there was something else influencing the boys and crime

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Madon et al. (2003)

Aim: - to look at the sFP  outside the educational setting with naturally false expectations
whether mothers’ expectations about their children’s future alcohol use would reflect actual alcohol use and whether the mothers’ expectations would limit the SFP

Procedure:505 mother-child pairs, 7th graders in the US (233 girls/ 272 boys)

- A longitudinal survey involved using questionnaires/interviews, collecting corellational data

- The questionnaires assessed variables related to family, peers and substance misuse
- were visited again for an interview for information, then they completed a written questionnaire

Findings: - 52% of the correlation between the mother’s expectation and the actual alcohol use of the child is down to maternal expectations, 48% down to SFP effects
- The relationship was stronger for children with high self-esteem than those with low self-esteem.

Conclusions: - Children with high self-esteem were more susceptible to self-fulfilling prophecies than those with low selfesteem. No evidence of effect from social class or family income.

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Madon et al. (2003) Evaluation

+  Mothers’ expectations are naturally-occurring, this is a naturalistic study to some extent

+ The longitudinal design helps to show that the DV does not cause the IV – whereas in this longitudinal study, some extent to cause-and-effect can be made

+  A large amount of data was gathered and a large ppt sample was used to identify any other factors which could have influenced the results

-  naturalistic studies like this one do not produce cause-and-effect conclusions like experiments do, and so it is hard to be sure about the SFP

-  Perhaps there was a third variable not considered that may have affected both the mothers’ expectations and the children’s actual future alcohol use

-  There were some differences in the questionnaires, for example mothers were asked if they thought the children would regularly drink, children would asked if they ever drank, so the comparison may not have been fair

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Evaluation of the SFP as an explanation of crime

+  there has been a lot of research into the SFP in educational contexts, as well as other areas such as alcohol use (Madon et al.) and crime (Jahoda) which have shown the effects of labelling

+  Madon suggests that people with high self-esteem are more likely to be affected by their parents’ predictions and she suggests that social class is not a factor in whether the parent-child relationship leads to the prophecy

+ if we know what causes SFP, we can learn to control/prevent it which could decrase crime

-  much of the research into the self-fulfilling prophecy has been in education, the teacher-child relationship being a special one where expectations may be fulfilled, however, other relationships may not have the same effect

-  the problem with studying effects of labelling at an individual level is finding false belief, which explains why there are few psychological studies into labelling and the self-fulfilling prophecy

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Evaluation of SLT as an explanation of crime

+  There is a lot of evidence to show that behaviour does get imitated, including evidence to show that aggressive behaviour is often copied (Bandura, Ross and Ross)

+  The theory has a practical application as the principles can be used to rehabilitate offenders, using good role models to reinforce appropriate behaviours with appropriate reinforcements to change the ways of criminals

-  The theory does not look at individual differences, only at how an individual is affected by social factors, and so biological aspects are not considered in this explanation

-  The theory does not provide an explanation for opportunistic crime which has not been observed and learnt first (so mainly applies to light crimes such as theft and aggression, rather than murder and ****)

-  most studies into SLT are observations and so may lack validity as variables are not tightly controlled

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My Practical

Aim: to investigate into the reliability of EWT by summarising two articles

Procedure: - find articles by looking on respected, reliable websites

- read article through once 

- read it through again and highlight key points about EWT

- using highlighted sections, summarise the articles

- read through article again to check it

Findings:

Conclusions: - EWT isn't reliable due to illumination

- EWT is not reliable and should be recorded and not be solely relied upon in court (e.g. be supported by DNA evidence)

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