Evaluating E-commerce system security using fuzzy multi-criterion decision-making

In the development of E-Commerce, security has always been the core and key issue. To aim at the assessment of E-Commerce security, in order to efficiently handle uncertain information in the process of decision making, a new fuzzy multi-criteria decision-making (MCDM) method is presented based on fuzzy sets theory (FST) and Dempster-Shafer evidence theory (DST). First, a hierarchical structure of E-Commerce security is established. Second, the ratings of the third level criteria and the importance weights of the first level criteria, given by the experts, are expressed in trapezoidal (or triangular) fuzzy numbers. The ratings can be transformed into basic probability assignments (BPA) based on an improved similarity measure of generalized fuzzy numbers we proposed, combining the BPAs from bottom to top using Dempster's combination rule. At last, the importance weights can be transformed into discounting coefficients and the BPAs of the first level criteria can be fused using the discounting rule to obtain the final assessment decision. An illustrative example is given to show that the proposed method can be applied to the security evaluation for the complex E-Commerce system and provides the scientific and consensus evaluated results as well.