In the case the final uncertainty remains asymmetric,
the authors should provide detailed information about the
`shape of the uncertainty', giving also most probable value,
probability intervals, and so on.
But the best estimate of the
*expected value and standard deviation should
be always given* (see also the *ISO Guide* [14]).

To conclude, I would like to leave the final word to my preferred quotation with whom I like to end seminars and courses on probability theory applied to the evaluation and the expression of uncertainty in measurements:

Guide``Although this

provides a framework for assessing uncertainty, it cannot substitute for critical thinking, intellectual honesty, and professional skill. The evaluation of uncertainty is neither a routine task nor a purely mathematical one; it depends on detailed knowledge of the nature of the measurand and of the measurement. The quality and utility of the uncertainty quoted for the result of a measurement therefore ultimately depend on the understanding, critical analysis, and integrity of those who contribute to the assignment of its value.''[14]

It is a pleasure to thank *Superfaber*
(Fabrizio Fabbri in *hepnames*) for helpful
discussions on the subject and for his *super*vision of the
manuscript.