Data Analysis and Research Methods

Course Description and Syllabus

The Cartoon Activity #7 - Part 1, Activity 7

This lesson is adapted from an activity developed by Dr. Jo Engle, University of Wisconsin, Eau Clair, Wisconsin

Key Purposes:

1. Students can calculate and interpret correlation using Spearman’s rank correlation.
2. Students can explain why correlation does not necessarily mean cause-and-effect.
3. Students can explain why the correlation coefficient should be used in conjunction with graphics.

To see a Quick Time Movie of the Cartoon Activity, Click the above image. File size may be large, please allow enough time for the download.

Description:

The Cartoon Activity is used to introduce the idea of correlation. It is suggested that maybe the teacher has a "weird" sense of humor (weird meaning different from that of the students). As a way of deciding, students are asked to rank a set of 8 cartoons, while the teacher does likewise. Each student then calculates a rank correlation; the interpretation of the coefficient is explained. Correlation issues, such as sample size, randomness of samples, linearity, and cause and effect, are discussed. Students are also shown how to get the Pearson’s correlation coefficient with their TI-83, but are not shown the formula. They are told that just as they have different ways (mean, median, and mode) to indicate the central location of data, there are different ways to calculate the correlation coefficient, and that the Pearson’s coefficient doesn’t require ranking the data. Students are encouraged to do a rank correlation of cartoons, (or current movies or music) with their parents, too.