A survey was taken of students at a large university in the fall of 2003 who were enrolled in one of three introductory statistics courses: Stat 200, commonly taken by students in the social sciences; Stat 1000, taken by students in the natural sciences; and Stat 1100, taken by business majors. We would like to explore whether the courses differ in terms of the percentages of males and females enrolled, and so we will treat "Course" as the explanatory variable, and "Gender" as the response.
a. Explain why "Course" should be treated as a categorical variable, in spite of the fact that it takes number values.
b. Use software to access the student survey data. Report the percentage of females in Stat 200, Stat 1000, and Stat 1100.
c. Which course has the highest percentage of females and which has the lowest?
d. Should we assume that the difference in percentages is due to chance, or is there a good possibility that males and females would have a tendency to major in different subject areas?