This exercise has been used successfully by more than a thousand students is an introductory college course, and it probably could be equally successful with high school students. Census tract data are used in a simulated research project. Quality of housing in the dependent variable (whose distribution we wish to “explain”), with owner-occupancy and age of housing as independent (or “explanatory”) variables. The distribution of the three variables is compared visually (by maps) and statistically (by scattergrams). A regression line is placed on the better scattergram, and residual values are mapped to provide a basis for the formulation of better working hypotheses. © 1972 Taylor and Francis Group, LLC.