1. Car Evaluation: Derived from simple hierarchical decision model, this database may be useful for testing constructive induction and structure discovery methods. 2. Lenses: Database for fitting contact lenses 3. MONK's Problems: A set of three artificial domains over the same attribute space; Used to test a wide range of induction algorithms 4. Trains: 2 data formats (structured, one-instance-per-line) 5. Reuters-21578 Text Categorization Collection: This is a collection of documents that appeared on Reuters newswire in 1987. The documents were assembled and indexed with categories. | 
