For each of the five data sets described, answer the following three questions and then use Figure 2.2 ( on this page) to select an appropriate graphical display.
Question 1: How many variables are in the data set?
Question 2: Is the data set categorical or numerical?
Question 3: Would the purpose of a graphical display be to summarize the data distribution, to compare groups, or to investigate the relationship between two numerical variables?
Data Set 1: To learn about the reason parents believe their child is heavier than the recommended weight for children of the same age, each person in a sample of parents of over-weight children was asked what they thought was the most important contributing factor. Possible responses were lack of exercise, easy access to junk food, unhealthy diet, medical condition, and other.
Data Set 2: To compare commute distances for full- time and part- time students at a large college, commute distance was determined for each student in a random sample of 50 full- time students and for each student in a random sample of 50 part- time students.
Data Set 3: To learn about how number of years of education and income are related, each person in a random sample of 500 residents of a particular city was asked how many years of education he or she had completed and what his or her annual income was.
Data Set 4: To see if there is a difference between faculty and students at a particular college with respect to how they commute to campus (drive, walk, bike, and so on), each person in a random sample of 50 faculty members and each person in a random sample of 100 students was asked how he or she usually commutes to campus.
Data Set 5: To learn about how much money students at a particular college spend on textbooks, each student in a random sample of 200 students was asked how much he or she spent on textbooks for the current semester.