One of the key points in modern measurement science is the evaluation of measurement uncertainty, according to the definition given by the International Vocabulary of Metrology (VIM) [1] and the procedure recommended by the Guide to the Expression of Uncertainty in Measurement (GUM) and its supplements [2]–[4]. According to these documents, when several sources of uncertainty are present, the related standard uncertainties shall be quadratically combined, and the covariances must be considered, if present [2].

Read more in the article published by the Instrumentation & Measurement Magazine.