To Plot or Not to Plot: An Exercise on Understanding and Comparing Datasets

As managers face a flood of data, it is very important that they effectively analyze and interpret the available data to make decisions. Plotting data will help them in their analysis and interpretation of raw data. The same is true for students in business programs. However, students in business programs (and managers) often do not see the importance of plotting data. This exercise presents a typical classroom scenario in which the professor of data visualization quotes statistician John W. Tukey to his students and tries to drive home the importance of plotting data. A representative student understands about presenting summary statistics and running some statistical tests, but questions the usefulness of plotting points as well. The professor must decide how to teach the class about the merits of plotting data. The professor gives the student an assignment with data and instructions, and tells the student to report the class the next day. The student is unaware that he has been given the Anscombe quartet, and he becomes convinced of the benefits of plotting data.

By working through the exercise and assignment questions, students will have the opportunity to do the following:<ul><li>Understand the importance in data analysis and interpretation of plotting the data</li><li>Demonstrate the applications of plotting the graphs</li><li>Understand mean, standard deviation, and regression coefficients</li><li>Demonstrate the concept of the Anscombe quartet.</li></ul>

• plotting data
• first-order and second-order moments
• data visualization
• bivariate analysis
• regression