Differences between statistical unertainty and modeling uncertainty are bri
efly discussed. It is pointed out that, when different models are proposed
for the interpretation of reality, the uncertainty cannot be described in t
erms of mean value and coefficient of variation. The important question is:
which of the proposed models is more reliable than the others?
The attention, then, is concentrated on the comparison between different mo
dels proposed for the estimate of the required quantity, looking for a crit
erion leading to the selection of the most reliable one.
A criterion for comparison of different models is suggested. In the example
of application considered in this paper, it proved to be effective, so tha
t the continuation of numerical experiments, exploring different and more c
omplex situations, seems promising.