There being no such thing as a perfect measurement, Experimental Uncertainty expresses the result of analytically propagating measurement “errors”1 from the instrument to a final, integrated result. Propagation is often not simple, and often depends on the detailed physics relationship between properties than can be instrumented and properties that cannot be instrumented.
The National Institute of Standards and Technology (NIST) maintains a very good reference on this subject at http://physics.nist.gov/cuu/Uncertainty/index.html. I’ve also found “Experimentation and Uncertainty Analysis for Engineers”2 to be very helpful.
Footnotes- These aren’t really “errors” per se, but the “uncertainty“.[↩]
- Colman, Hugh W. and W. Glenn Steele, Jr; John Wiley & Sons, New York, 1989 (ISBN 0-471-63517-0).[↩]