Near-infrared spectroscopy（NIR） was employed to determine the quality of walnut oil. Multivariate scattering correction（MSC） and combination of standard normal variate and de-trend（SNV-DT） were separately used for preprocessing. Successive projection algorithm（SPA） and combination of competitive adaptive reweighted sampling algorithm and partial least squares method（CARS-PLS） were separately used for extraction of characteristic wavelengths. Particle swarm optimization（PSO） and genetic algorithm（GA） methods were separately used fo...
