Abstract: The calibration reference standard of a determination apparatus is determined and the error model is found and the determination results from which the effects of systematic error have been removed are displayed. If the operator is satisfied with these determination results, calibration is terminated. Moreover, if the operator is not satisfied with these determination results, the desired parameter of the calibration reference standard is re-determined, the error coefficient is found and the determination results from which the systematic error has been removed are immediately re-displayed. These determination results are retained until calibration is terminated and if re-determination of a calibration reference standard has been performed during the calibration operation, the determined values are retained so that the most recent determination results can be referenced.