Transfer of spectra by means of local correction

Frequently, in NIRS (Near Infra-Red Spectroscopy) a multivariate regression model for instrument calibration developed on a master instrument must be used also on other (server) instruments. The instruments are more or less d ifferent. Because of these differences, the regression model developed on t he master instrument can't be applied or gives bad results. Several procedures have been suggested to overcome this problem. Shenk and Westerhaus suggested the transfer of spectra, i.e. the reproduction of the spectra of the master instrument from that of the server, by means of a loc al correction procedure, known as the "patented algorithm". This procedure seems very suitable in the case the main difference between the instruments is due to a shift in wavelength. In this work, some points of the original procedure have been modified, bot h the method to evaluate the shift and the subsequent treatment. The local transfer, with these changes and with those previously suggested by Bouvere sse, is greatly improved. Results reported refer to real and simulated data.