Feasibility Study on the Use of a Portable NIR Spectrometer and Multivariate Data Analysis to Discriminate and Quantify Adulteration in Fertilizer

Table 2

The influence of preprocessing technique on identification models (fertilizer A).

Models	Evaluation	Preprocessing treatment at 5PCs
		Raw		SNV		FD		SD
		Train	Test	Train	Test	Train	Test	Train	Test
RF	Accuracy	93.70	94.70	93.50	94.60	96.50	96.50	93.70	94.70
	Error rate	6.30	5.30	6.50	5.40	3.50	3.50	6.30	5.30
	Sensitivity	96.40	96.00	95.30	94.00	96.80	97.60	96.40	96.00
	Specificity	99.70	99.70	98.90	99.50	98.50	99.20	99.70	99.70
SVM	Accuracy	92.30	92.30	98.50	98.50	99.20	99.50	92.30	92.30
	Error rate	7.70	7.70	1.50	1.50	0.80	0.50	7.70	7.70
	Sensitivity	96.30	97.10	98.50	96.80	99.20	99.50	96.30	97.10
	Specificity	92.30	92.30	97.50	97.50	99.20	99.50	92.30	92.30