A method of Grade division based on Set Pair Analysis

As a branch of Group Decision-Making Method, Grade division plays an important role in many applications such as hazard assessment, quality evaluation, and performance inspection and so on. At present, the most popular grade division method is fuzzy comprehensive evaluation, which determines the decision objects´ grade through analysis of evaluation vector. One problem with this approach is that it only considers the grades´ own values and pays little consideration to the relationships among them. In this paper, the investigation introduces the method of Set Pair Analysis (SPA), which analyzes the relationships among grades from aspects of identity, discrepancy and contrary to make the division result more in line with actual situation.