TY - JFULL AU - Chen Wu and Lijuan Wang PY - 2017/4/ TI - Studies on Properties of Knowledge Dependency and Reduction Algorithm in Tolerance Rough Set Model T2 - International Journal of Computer and Information Engineering SP - 413 EP - 419 VL - 11 SN - 1307-6892 UR - https://publications.waset.org/pdf/10008467 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 123, 2017 N2 - Relation between tolerance class and indispensable attribute and knowledge dependency in rough set model with tolerance relation is explored. After giving definitions and concepts of knowledge dependency and knowledge dependency degree for incomplete information system in tolerance rough set model by distinguishing decision attribute containing missing attribute value or not, the result of maintaining reflectivity, transitivity, augmentation, decomposition law and merge law for complete knowledge dependency is proved. Knowledge dependency degrees (not complete knowledge dependency degrees) only satisfy some laws after transitivity, augmentation and decomposition operations. An algorithm to solve attribute reduction in an incomplete decision table is designed. The correctness is checked by an example. ER -