In assessing fuzzy numbers to model imprecise data associated with random experiments,
trapezoidal fuzzy numbers are often considered. Such an assessment is mainly due to
easing both interpretation and computation. This becomes especially noticeable when those
assessing fuzzy numbers to data have a weak knowledge, low background and little or no
expertise in using fuzzy sets (as it happens when questionnaires whose responses involve a
free fuzzy rating are conducted), since the required training to explain the meaning and use …