Abstract: Considering the complexity of data in multi-source covering information systems and the inequality between individual information systems, this paper introduces the induced covering rough set and assigns weight values to each single information system’s attribute, and, consequently, proposes a weighted generalized multi-granulation rough set of multi-source covering information systems. Firstly, it defines the calculation method of attribute’s weight. Then, it gives complete upper and lower approximations of the model, and acquires the corresponding decision rule. Finally, it verifies the validity of the model through an example analysis. The experimental results show that the model has a better ability to classify the target set, and its fault tolerance can be further improved with appropriate adjustment of the threshold.

Key words: multi-source information system, generalized multi-granulation, covering rough set