Читать книгу Planning and Executing Credible Experiments - Robert J. Moffat - Страница 51

Physical measurements are subject to errors from many sources. Try as we may, we can never entirely correct for all the possible error sources. Sometimes we may simply decide it is too expensive to correct for a small possible error. Sometimes, we don’t know an error is present. In the best of situations, we must admit that even our corrected value is probably not exact. To deal with this situation we need a quantitative way to estimate the possible residual error and to describe it to potential users of the data. This problem was recognized by Airy (1879), who used the term “uncertainty,” which he defined as “The possible value that the residual error may have.”

Most engineering experiments involve several measurements, and the result of the experiment is derived from the measured values using a set of equations called the “data interpretation program.” The challenge is to estimate the uncertainty in the derived result as a consequence of the recognized uncertainties in the measurements.