On identity-discrepancy-contrary connection degree in SPA and its applications

As a kind of new uncertainty theory, the set pair analysis (SPA) researches certainties and uncertainties from the whole. The main idea of SPA is: (1) Every system is comprised of certainty knowledge and uncertainty knowledge; (2) Certainties and uncertainties are inter-related, inter-influenced, inter-restricted, and inter-transformed even under certain condition, in every system; (3) A computation formula (identity-discrepancy-contrary (IDC) connection degree formula) which can embody the above idea fully is used to depict uniformly all kinds of uncertainties such as fuzzy uncertainty, random uncertainty, indeterminate-known uncertainty, unknown and unexpected incident uncertainty, and uncertainty which is resulted from imperfective information. This paper introduces the concepts and provides the applications of IDC connection degree and IDC connection number in SPA.