Many years ago, Smith College, a residential college, switched to an unusual academic schedule that made it fairly easy for students to take most or all of their classes on the first three days of the week. (Smith has long since abandoned this experiment.) At the time, the infirmary staff wanted to know about after-hours use of the infirmary under this schedule. They gathered data for an entire academic year, recording the time and day of the week of each after-hours visit, along with the nature of the problem. which they later classified as belonging to one of four categories: A visit to the infirmary was unnecessary for the problem, the problem required a nurseâ€™s attention, the problem required a doctorâ€™s attention, the problem required admission to the infirmary or to the local hospital. The results appear in Display 10.79.
a. Construct a plot to display these data.
b. Are there any interesting trends in the table? What might explain them?
c. Could you use a test of independence on these data? A test of homogeneity? Does the design of the study fit the conditions of these tests?
d. Perform the test you think is best, giving any necessary cautions about your conclusion.
Â e. How might you group the data to see whether the data for the weekdays when students attend class differ from the data for the weekdays when students donâ€™t attend class?
Â f. Perform a chi-square test on your regrouped data.