A plurality of first measured values (xi) are obtained by respectively measuring a plurality of measuring objects in a plurality of first measuring systems and a plurality of second measured values (yi) are obtained by respectively measuring the plurality of measuring objects in a plurality of second measuring systems, and a combination of a first measured value and a second measured value corresponding to each other is obtained as a sample point (Pi). A transformation function representing a relationship between a first reconstituted system derived from the plurality of first measuring systems and a second reconstituted system derived from the plurality of second measuring system is obtained statistically processing a plurality of sample points of the plurality of measuring objects. Subsequently, a transformed value (τi) is obtained by transforming a second measured value (yi) with the transformation function.