Our defect dataset, comes from PROMISErepository. This data refers to open-source Java systems such as ant, camel, ivy, jedit, log4j, lucene, poi, synapse, velocity and xerces. We selected these datasets since they have at least three consecutive releases (where release i was built before release i+1). This will allow us to build defect predictors based on the past data and then predict (test) defects on future version projects, which will be a more practical scenario.