Optimization of Bi₂O₃, TiO₂, and Sb₂O₃ Doped ZnO-Based Low-Voltage Varistor Ceramic to Maximize Nonlinear Electrical Properties

Table 3

ANOVA of quadratic model.

Source	Sum of squares	Degree of freedom	Mean square	-value	value	Suggestion
Model	100.24	9	11.14	28.79	<0.0001	Significant
	2.89	1	2.89	7.47	0.0211	—
	20.30	1	20.30	52.46	<0.0001	Significant
	0.55	1	0.55	1.41	0.2623	—
	0.018	1	0.018	0.046	0.8346	—
	0.14	1	0.14	0.37	0.5590	—
					0.9715	—
	10.30	1	10.30	26.62	0.0004	Significant
	23.70	1	23.70	61.24	<0.0001	Significant
	54.58	1	54.58	141.06	<0.0001	Significant
Residual	3.87	10	0.39
Lack of fit	2.72	5	0.54	2.35	0.1846	Not significant
Pure error	1.15	5	0.23
Corrected total	104.11	19
-squared		0.9628	Standard deviation		0.62
Adjusted ^2		0.9294	Coefficient of variation %		9.84
Predicted ^2		0.7793	PRESS		22.98
Adequate precision		13.279