Nearly Parallel Lines in Residual Plots

In this department The American Statistician publishes articles, reviews, and notes of interest to teachers of the first mathematical statistics course and of applied statistics courses.The department includes the Accent on Teaching Materials section; suitable contents for the section are described under the section heading. Articles and notes for the department, but not intended specifically for the section, should be useful to a substantial number of teachers of the indicated types of courses or should have the potential for fundamentally affecting the way in which a course is taught.When the residuals from a generalized linear model are to be plotted against the fitted values, the plot can be made to resemble that for a normal error model by transforming the fitted values to the constant-information scale.