Using Adjustment Functions in the Lab taking into Account the Correlation between their Parameters

Abstract

An adjustment is carried out to obtain the adjustment parameters that define a mathematical function that is used to obtain interpolated and extrapolated values. The calculated value obtained by means of the adjustment function will be reported as the uncertainty of this value. The commercial calculus programs can be used to adjust curves they reporting directly the value of parameters and their uncertainties, but they don't report the covariance among their parameters, for this reason the estimation of the uncertainties associated to these calculated magnitudes are not successful. In this work are presented the results obtained in the educational laboratory when calculating the uncertainties using the matrix method and keeping in mind the covariances among the adjustment parameters.