Quantitative Classification of Quartz by Laser Induced Breakdown Spectroscopy in Conjunction with Discriminant Function Analysis

Table 1

Variables that are used in the analysis at each step.

Variables entered/removed
Step	Entered	Wilks’ lambda
		Statistic	df1	df2	df3	Exact				Approximate
						Statistic	df1	df2	Sig.	Statistic	df1	df2	Sig.
1	Si I (243.51)/Li I (670.79)	0.025	1	4	148.000	1419.00	4	148.000	0.000
2	Si I (250.69)/Li I (670.79)	0.002	2	4	148.000	818.586	8	294.000	0.000
3	Si I (243.52)/Na I	0.000	3	4	148.000					590.966	12	386.571	0.000
4	Si I (288.15)/Li I (670.79)	0.000	4	4	148.000					496.521	16	443.620	0.000
5	Si I (250.69) Na I	0.000	5	4	148.000					408.230	20	478.544	0.000
6	Si I (263.12)/Li I (670.79)	0.000	6	4	148.000					341.600	24	500.077	0.000
7	Si I (288.15)/Na I	0.000	7	4	148.000					293.669	28	513.410	0.000
8	Si I (263.12)/Li I (670.79)]	0.000	8	4	148.000					256.773	32	521.577	0.000