Abstract
It is known that some uncertain sets have membership functions, and some do not. How do we judge whether an uncertain set has a membership function? In order to answer this question, this paper presents a concept of totally ordered uncertain set, and shows that totally ordered uncertain sets always have membership functions if they are defined on a continuous uncertainty space. In addition, some criteria for judging the existence of membership functions for uncertain sets are provided. Several inspiring examples and counterexamples are also documented in this paper.
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This work was supported by National Natural Science Foundation of China Grant No.61573210.
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Liu, B. Totally ordered uncertain sets. Fuzzy Optim Decis Making 17, 1–11 (2018). https://doi.org/10.1007/s10700-016-9264-6
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DOI: https://doi.org/10.1007/s10700-016-9264-6