Researchers have therefore adopted an empirical,
multivariate approach (Osborne and Fearn, 1986).
This assumes that a foliar spectrum is the sum of
the absorption features of each chemical, weighted
by its concentration. In its simplest form, stepwise
regression can be used to locate wavebands in the
foliar spectra in which there is a high correlation
between reflectance and chemical concentration.
Reflectance in these wavebands can then be used