When
we transfer a calibration or a database from one instrument to other, we know
in advance that we have a sample presentation error in the instrument where the
calibration comes from, and it is important to know it before you interpret the
statistics.
In
this case I know the predictions from several samples acquired in two repacks,
so the sample result we consider is the average, but in this case we are
interested in the individual results of every repack (2 results in this case).
So I can calculate the difference of both results for every repack and after
that (with all the values) I can calculate the standard deviation to get what I
can consider the repacking error.
Notice that I will have a value of standard deviation for every parameter.
So
I can compare this value with the errors the monitor function gives to me.
The
error packaging for the moisture in wheat for a NIR5000 with natural product
cell was 0,11. After an standardization to transfer the database to a DS2500 I
get an RMSEP error of 0,21, but I can see that maybe due to the samples chosen for
the standardization I have an slope which affects specially to the samples with
high moisture. But I can see also that the error once than the slope and
intercept are corrected is Sres=0,12 , very similar to the repacking error, so
there is a good improvement which makes me challenge to try a better standardization
to improve the calibration or database transfer.
No hay comentarios:
Publicar un comentario