// Randomize on a copy of the original dataset
Instances runInstances = new Instances(m_Instances);
Random random = new Random(run);
runInstances.randomize(random);
if (runInstances.classAttribute().isNominal()) {
runInstances.stratify(m_NumFolds);
}
// Add in some fields to the key like run and fold number, dataset name
Object [] seKey = m_SplitEvaluator.getKey();
Object [] key = new Object [seKey.length + 3];