The Experimenter 13 CHAPTER The Explorer and Knowledge Flow environments help you determine how well machine learning schemes perform on given datasets. But serious investigative work involves substantial experiments--typically running several learning schemes on different datasets, often with various parameter settings--and these interfaces are not really suitable for this. The Experimenter enables you to set up large-scale experiments, start them running, leave them and come back when they have fin- ished, and then analyze the performance statistics that have been collected. They automate the experimental process. The statistics can be stored in ARFF format, and can themselves be the subject of further data mining. You invoke this interface by selecting Experimenter from the choices in the right panel in Figure 11.3(a).