Does the location of your seat in a classroom play a role in attendance or grade? To answer this question, professors randomly assigned 400 students* in a general education physics course to one of four groups. The 100 students in group 1 sat 0 to 4 meters from the front of the class, the 100 students in group 2 sat 4 to 6.5 meters from the front, the 100 students in group 3 sat 6.5 to 9 meters from the front, and the 100 students in group 4 sat 9 to 12 meters from the front.

(a) For the first half of the semester, the attendance for the whole class averaged 83%. So, if there is no effect due to seat location, we would expect 83% of students in each group to attend.

The data show the attendance history for each group. How many students in each group attended, on average? Is there a significant difference among the groups in attendance patterns? Use the α = 0.05 level of significance.

(b) For the second half of the semester, the groups were rotated so that group 1 students moved to the back of class and group 4 students moved to the front. The same switch took place between groups 2 and 3. The attendance for the second half of the semester averaged 80%. The data show the attendance records for the original groups (group 1 is now in back, group 2 is 6.5 to 9 meters from the front, and so on). How many students in each group attended, on average? Is there a significant difference in attendance patterns? Use the α = 0.05 level of significance. Do you find anything curious about these data?

(c) At the end of the semester, the proportion of students in the top 20% of the class was determined. Of the students in group 1, 25% were in the top 20%; of the students in group 2, 21% were in the top 20%; of the students in group 3, 15% were in the top 20%; of the students in group 4, 19% were in the top 20%. How many students would we expect to be in the top 20% of the class if seat location plays no role in grades? Is there a significant difference in the number of students in the top 20% of the class by group?
(d) In earlier sections, we discussed results that were statistically significant, but did not have any practical significance. Discuss the practical significance of these results. In other words, given the choice, would you prefer sitting in the front or back?

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