%0 Journal Article %T Uncertainty Interval Evaluation Using the Chi-Square and Fisher Distributions in the Measurement Process %A Marcantonio Catelani %A Andrea Zanobini %A Lorenzo Ciani %J Metrology and Measurement Systems %D 2010 %I %R 10.2478/v10178-010-0017-5 %X Referring to the Guide to the Expression of Uncertainty in Measurement (GUM), the paper proposes a theoretical contribution to assess the uncertainty interval, with relative confidence level, in the case of n successive observations. The approach is based on the Chi-square and Fisher distributions and the validity is proved by a numerical example. For a more detailed study of the uncertainty evaluation, a model for the process variability has been also developed. %K measurement uncertainty %K confidence level %K statistical distributions %U http://versita.metapress.com/content/42u4312333j53046/?p=c548da5d54c54ddaaf7edb780f7df068&pi=4