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.