
Concept explainers
Final Exam Grades The data that follow are final exam grades for two sections of statistics students at a community college. One class met twice a week relatively late in the day; the other class met four times a week at 11 a.m. Both classes had the same instructor and covered the same content. Is there evidence that the performances of the classes differed? Answer by making appropriate plots (including side-by-side boxplots) and reporting and comparing appropriate summary statistics. Explain why you chose the summary statistics that you used. Be sure to comment on the shape of the distributions, the center, and the spread, and be sure to mention any unusual features you observe.
11 a.m. grades: 100, 100, 93, 76, 86, 72.5, 82, 63, 59.5, 53, 79.5, 67, 48, 42.5, 39
5 p.m. grades: 100, 98, 95, 91.5, 104.5, 94, 86, 84.5, 73, 92.5, 86.5, 73.5, 87, 72.5, 82, 68.5, 64.5, 90.75, 66.5

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