Summarize the basic concept and result of meta-analysis. Mention the statistic used and describe the formula used to calculate it. What advantage does meta-analysis provide researchers in personality theory?

What will be an ideal response?

Answer: The two main advantages of meta-analysis are that it allows a researcher to combine the results of many different studies and that it provides an estimate of the size of the effect of the independent variables in question. When an experiment is conducted comparing two or more groups on one or more independent variables, a statistic such as a t-test will tell you if the differences between the groups on the dependent variable(s) are significant or not. The meta-analysis statistic (d) will give you an estimate of the effect size. This is particularly important when looking at differences between men and women because with a large sample some very small differences will be statistically significant. Meta-analysis lets you look at many studies that have looked at the same variables and see if by combining their results the effect still holds and lets you estimate how large the effect is in a range from “trivial” to “very large”. The d statistic is basically the average of one group minus the average of the other group (in this case, males vs. females) on a dependent variable, divided by the average standard deviation of all the scores combined.