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A large company would like to assess the impact of using a professional trainer to conduct a confidence-building workshop with their salespeople. A sample of 16 workers is obtained. Half of them (n = 8) attend the workshop, and the other half (n = 8) do not, serving as a control group. Two weeks later, each of the participants is given a questionnaire measuring their level of self-confidence. The data are as follows:
Controls Workshop
x̅ = 17.5 x̅ = 22.7
SS = 100 SS = 124
Which statistical test would you use to examine if there is a significant difference in self-confidence between those people who attended the workshop and those who did not?
a. one sample t test
b. two sample t test
c. repeated measures t test
d. ANOVA
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