315 
elated to the first 
cal interpretation is 
GUM suggests to 
rocedures, only in 
aspectively: 
■fa. (in the case the 
terms should be 
second category is 
quality”, aimed at 
<x,,s(x/)> can be 
h other. The formal 
and s(Xi)=s(Xj), is 
;ase, and different, 
proposed, typically 
tation of the terms 
s assumed as the 
Its could be judged 
se their intersection 
; not even mention 
ns. For important 
the procedures to 
ss the results of the 
n open issue. 
* the measurand value, the singleton x, is maximally 
specific but uncertain, with uncertainty s(x); 
* the measurand value, the interval [x-s(x),x+s(x)j, is not 
completely specific but considered certain. 
The same empirical information, as obtained by the 
measurement, can be represented by suitably balancing 
the specificity and the certainty of the result (for example, 
if the statement A cannot considered certain on the basis 
of the available information, then 
C = “this is a more-than-100-page book” 
could be adopted, less specific but more certain than A. In 
the case the object is factually a 120-page book, then A 
would not be “truer” than C, but more specific, and 
therefore more informative, than it). 
As a synthesis: 
* measurement results are neither specific nor non 
specific, and neither certain nor uncertain; 
* they are neither singletons-with-uncertainty-degrees nor 
intervals; 
* but they can interpreted in either way, in view of specific 
applications. 
7. REFERENCES 
Bridgman P.W., 1959. How much rigor is possible in 
physics? In: Henkin et al. (eds.), The Axiomatic method, 
North-Holland. 
CIPM, BIPM, 1981. Proc. Com. Int. Poids et Mesures, 49, 
8-9, 26 (in French) (also reported in the Introduction of the 
GUM). 
ISO, et al., 1993. Guide to the expression of uncertainty in 
measurement. International Organization of 
Standardization, Geneva. 
Mari, L., Zingales, G., 1999. Uncertainty in measurement 
science. In: Proceedings of the IMEKO TC7 Workshop, 
Kyoto. 
Taylor N., Kuyatt C., 1997. Guidelines for Evaluating and 
Expressing the Uncertainty of NIST Measurement 
Results. NIST Technical Note 1297 (also available in the 
web: physics.nist.gov/Pubs/guidelines/contents.html). 
UNI, 1984. Misure e misurazioni. Termini e definizioni 
fondamentali. Italian Standard UNI 4546. 
AS 
PECIFICITY 
of a measurement 
on of two distinct 
non-specificity”. An 
meaning of such 
nsider the following 
r an observer on a 
basis of the form of 
iately drawn: 
lust be true (in set- 
herefore A is more 
rtainty assignment 
and plausibly more 
c,s(x)>, admits two