title: Use of radial basis function networks and near-infrared spectroscopy for the determination of total nitrogen content in soils from Sao Paulo State.
abstract: Total nitrogen has been determined by using a model developed between the conventional chemical measurements and diffuse reflectance spectra in the near-infrared region. Samples (244) from different types of soils with total nitrogen contents ranging from 0.20 to 13.60% (m/m) were modeled by partial least-squares regression (PLS), multi-layer perceptron feed-forward networks (MLP) and radial basis function networks (RBFN). The RBFN model produced a better square error of prediction (SEP) of 0.048 and R(2) = 0.93 in a procedure that is simpler, faster and less dependent on the initial conditions.
authors.affiliation: Universidade Federal do Tocantins, Gurupi, TO, Brazil. fidencio@ufv.br
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Fidêncio
authors.forename: Ronei J
authors.initials: RJ
authors.lastname: Poppi
authors.forename: João C
authors.initials: JC
authors.lastname: de Andrade
authors.forename: Mônica F
authors.initials: MF
authors.lastname: de  Abreu