An Example of the Use of Graphics in Regression

Graphical techniques are powerful data analytic tools.We demonstrate the use of five such techniques in the context of regression analysis.These are stem-and-leaf plots, schematic plots, time-order plots, scatterplots, and probability plots.Our presentation shows that some fairly subtle anomalies in a regression problem can be diagnosed without undue emphasis on algebraic formulas.The implications of this thesis to the teaching of introductory statistics courses are discussed.