Briefly describe the logic of the analysis of variance or F-test for a single-factor random groups design.
What will be an ideal response?
There are two sources of variation in any random groups experiment. First, variation within each group can be expected because of individual differences among subjects who have been randomly assigned to a group. The second source of variation in the random groups design is variation between the groups. If the null hypothesis is true (no differences among groups), any observed differences among the means of the groups can be attributed to error variation (e.g., the different characteristics of the participants in the groups). Thus, the variation among the different group means, when the null hypothesis is assumed to be true, provides a second estimate of error variation in an experiment. If the null hypothesis is true, this estimate of error variation between groups should be similar to the estimate of error variation within groups. Thus, the random groups design provides two independent estimates of error variation, one within the groups and one between the groups. The ratio of these two estimates, as represented in the F-test, should be 1.0.
If the null hypothesis is false, that is, the independent variable has had an effect, there will be systematic differences in the means across the different groups of the experiment. This systematic variation will be added to the differences in the group means that are already present due to error variation. By creating a ratio (F-ratio) of variation between groups and variation due to individual differences, evidence can be obtained regarding the likelihood of systematic variation in the experiment.
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a. self-report personality inventories b. multiphasic personality inventories c. projective personality measures d. humanistic personality measures e. true-false personality indicators
When solving a problem, male and female brains look identical in brain scans.
Answer the following statement true (T) or false (F)
Teicher and colleagues (2002) studied the chronic activation of stress responses due to childhood trauma. The researchers found ____
a. no meaningful differences in brain structures between childhood trauma victims and those who suffered no abuse b. that the hippocampal and amygdalar volumes were very low c. that the activity in the amygdala increased the ability to remember clearly d. that the amygdala and hippocampus could hamper the brains ability to encode, store and retrieve memories
Which type of attitude measures is most vulnerable to impression management bias?
a. one-item measures b. evaluative priming c. implicit measures d. direct measures