Modeling Complex Concepts with Type-2 Fuzzy Sets: The Case of User Satisfaction of Online Services

  • Masoomeh Moharrer
  • Hooman Tahayori
  • Alireza Sadeghian
Part of the Studies in Fuzziness and Soft Computing book series (STUDFUZZ, volume 301)


Specific characteristics of human perception, like context-dependency, imprecision, and diversity, demand capable formal frameworks for modeling the human mind. This chapter discusses a two-phase method for deriving type-2 fuzzy sets that model human perceptions of the linguistic terms used in describing online satisfaction. In the first phase, we describe the identification of the determinants of user satisfaction of online tourism services. We will demonstrate how the decomposition of the satisfaction concept into a set of simpler, albeit covering subconcepts, would be used to calculate a type-1 fuzzy set model of an individual’s perception. In the second phase, type-2 fuzzy sets modeling online user satisfaction are derived based on the obtained type-1 fuzzy sets. The construction of type-2 fuzzy sets is based on the exploitation of the fuzzy approach to represent uncertainty and by stacking the α-planes calculated at different levels of confidence around the estimated mean values of the type-1 fuzzy set.



The authors would like to sincerely acknowledge Professor G. Degli Antoni from Universita Degli Studi di Milano, and the staff of the Beauvais airport, Paris, without their help the data collection would not have been completed.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Masoomeh Moharrer
    • 1
  • Hooman Tahayori
    • 1
  • Alireza Sadeghian
    • 1
  1. 1.Department of Computer ScienceRyerson UniversityTorontoCanada

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