DOE Case 2.xlsx

	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P
1	Run#	Run Order	A	B	C	R1	Ave.	Std.Dev.
2	1	1	-	-	-	5.0	5.0	-
3	2	3	+	-	-	30.0	30.0	-
4	3	2	-	+	-	6.0	6.0	-
5	4	6	+	+	-	33.0	33.0	-
6	5	4	-	-	+	4.0	4.0	-
7	6	5	+	-	+	3.0	3.0	-
8	7	8	-	+	+	5.0	5.0	-
9	8	7	+	+	+	4.0	4.0	-
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13	Reference Key to Factor Selection
14	Factor A = Your factor:						Concentration of coagulant added				; B =	Treatment temperature			; C =	Stirring speed
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19	Calculating the Significance of Main Effects (Solving for Means)
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21	Factor A		Runs Where A is + :	30	+	33	+	3	+	4	=	70	/ 4 = Ave=	17.5	+
22			Runs Where A is - :	5	+	6	+	4	+	5	=	20	/ 4 = Ave=	5.00	-
23													Total Effect = Difference =	12.50
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25	Factor B		Runs Where B is + :	6	+	33	+	5	+	4	=	48	/ 4 = Ave=	12	+
26			Runs Where B is - :	5	+	30	+	4	+	3	=	42	/ 4 = Ave=	10.50	-
27													Total Effect = Difference =	1.50
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29	Factor C		Runs Where C is + :	4	+	3	+	5	+	4	=	16	/ 4 = Ave=	4	+
30			Runs Where C is - :	5	+	30	+	6	+	33	=	74	/ 4 = Ave=	18.50	-
31													Total Effect = Difference =	-14.50
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34	Run#	Run Order	A	B	C	R1	Ave.	Std.Dev.
35	1	1	-	-	-	5.0	5.0	-
36	5	4	-	-	+	4.0	4.0	-		At LOW B, Average of low A=			4.5	-
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38	2	3	+	-	-	30.0	30.0	-		At LOW B, Average of high A=			16.5	+
39	6	5	+	-	+	3.0	3.0	-		At LOW B, total effect of A=			12
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42	3	2	-	+	-	6.0	6.0	-		At HIGH B, Average of low A=			5.5	-
43	7	8	-	+	+	5.0	5.0	-
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45	4	6	+	+	-	33.0	33.0	-		At HIGH B, Average of high A=			18.5	+
46	8	7	+	+	+	4.0	4.0	-		At HIGH B, total effect of A=			13
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57													The gradient of both lines are different by a little margin. Therefore there’s an interaction between A and B, but the interaction is small. If both lines are parallel, then there’s NO interaction
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70	Run#	Run Order	A	B	C	R1	Ave.	Std.Dev.
71	1	1	-	-	-	5.0	5.0	-
72	3	2	-	+	-	6.0	6.0	-		At LOW C, Average of low A=			5.5	-
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74	2	3	+	-	-	30.0	30.0	-		At LOW C, Average of high A=			31.5	+
75	4	6	+	+	-	33.0	33.0	-		At LOW C, total effect of A=			26
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78	5	4	-	-	+	4.0	4.0	-		At HIGH C, Average of low A=			4.5	-
79	7	8	-	+	+	5.0	5.0	-
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81	6	5	+	-	+	3.0	3.0	-		At HIGH C, Average of high A=			3.5	+
82	8	7	+	+	+	4.0	4.0	-		At HIGH C, total effect of A=			-1
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95													The gradient of both lines are different (one is + and the other is -). Therefore there’s a significant interaction between A and C
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