On an Exploratory Analysis of Contingency Tables

An inherent advantage to simple informative graphical displays is that the experience and intuition of the experimenter who collects the data can contribute to the statistician's data analysis. This is in contrast to numerical techniques where the experimenter gets- back from the statistician estimates of parameters derived under more or less valid assumptions. We present here some simple data analytic techniques for investigating two-way and three-way contingency tables. These techniques are demonstrated with data collected in an experiment at Bell Labora- tories.