meta analysis

Question 1

what is a meta analysis?

Answer 1

• using results from different studies about the same issue and studying them as a whole to look for an overall picture about the area of the study

Question 2

what is primary data?

Answer 2

• information observed or collected directly from first hand experience
• collected for the study currently being undertaken and specific to the aims

Question 3

what is secondary data?

Answer 3

• information that was collected for a purpose other than the current one e.g. government statistics

Question 4

what is a strength and a weakness of secondary data?

Answer 4

• strength = large amount of data available
• weakness = there may have been biases or methodological issues in the way it was gathered

Question 5

what is the order of steps when conducting a meta-analysis?

Answer 5

• define the research question
• perform the literature research
• select the studies
• extract the data
• analyse the data
• report the results

Question 6

what is an example of a meta analysis used in criminal psychology?

Answer 6

• steblay et al used a meta analysis to investigate pre trial publicity

Question 7

what emprirical studies into PTP have been conducted?

Answer 7

• fulero
• linz and pendrod

Question 8

what issues do the studies posed?

Answer 8

• PTP effects with final juror verdicts
• operationalised PTP in different ways so hard to compare

Question 9

what was the hypothesis common to the studies?

Answer 9

• jurors exposed to negative PTP will produce higher percentages of guilty verdicts than jurors exposed to neutral PTP

Question 10

what did the meta analysis help to overcome?

Answer 10

• extraneous error components
• statistical limitations of small samples

Question 11

what were two of the aims that stebly had for the research into PTP?

Answer 11

• determine the effect if any on negative PTP upon jurors judgement of defendants
• the conditions where PTP is most likely to occur

Question 12

what was the DV in the meta analysis?

Answer 12

• guilt/innocence of the defendant

Question 13

what was the sample used by stebly?

Answer 13

• 23 articles (18 published 5 unpublished)

Question 14

what did stebly find?

Answer 14

• PTP has a significant effect on subjects judgements regarding the guilt of the defendant
• effect size = 0.22

Question 15

what is a strength of meta analysis in terms of validity?

Answer 15

• collects a large sample of data from a vast array of different areas
• increases validity as it reduces the affect of anomalous results

Question 16

what is a strength in terms of ethics?

Answer 16

• researchers are not carrying out the research themselves so it avoids any ethical issues

Question 17

what is a weakness in terms of validity?

Answer 17

• there may be methodological issues which may affect conclusions drawn
• e.g. may be lack of control variables

Question 18

what is a strength of validity in terms of peer review?

Answer 18

• researchers often don’t include unpublished work so all findings are peer reviewed