Table 7.

Statistical test results of the multiple regression model having values measured by the oxidimetry method as response variables, values measured by the electrochemical method, values measured by the DO meter (mg/L), water temperature (degree Celsius), and the interaction between the electrochemical method and DO as explanatory variables

		Type III
Source	Degree of freedom	Sum of squares	Mean sum of squares	F ratio	p value
Electrochemical method	1	2.5041	2.5041	12891.5	< 0.0001
DO meter (mg/L)	1	0.0018	0.0018	9.18	0.0060
Water temperature (degree Celsius)	1	0.0003	0.0003	1.67	0.2088
Interaction between electrochemical method and DO	1	0.0014	0.0014	7.46	0.0119