One-Way ANOVA and post-hoc test using SPSS
An investigator is interested in the effects of stress on reaction time. She gives a reaction time test to three groups of subjects; one group that is under a great deal of stress, one group under a moderate amount of stress and a third group that is under almost no stress. Theory A suggests that subjects under a moderate amount of stress will perform better than subjects in either the very low or the very high stress groups. Theory B predicts that subjects in the high stress group will perform better than subjects in either the low stress or the moderate stress groups. Theory C predicts that subjects in the moderate stress condition will perform significantly more poorly than subjects in the low stress condition.
Please write a paragraph that summarizes the conclusions that the investigator is entitled to draw from these results. In this paragraph, be sure to make it clear how you handled the issue of conducting three planned comparisons. Also provide the ANOVA summary table for these results.
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High Stress
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Moderate Stress
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Low Stress
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6
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8
|
10
|
|
7
|
10
|
11
|
|
4
|
11
|
8
|
|
5
|
7
|
6
|
|
6
|
12
|
13
|
|
3
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11
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12
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