Operators and Machines
I would like the response to the sample questions below in excel format, so that I can see the formulas used.
The quality director for a clothing manufacturer wants to study the effect of operators and machines on the breaking strength (in pounds) of wool serge material. A batch of the material is cut into square-yard pieces and these are randomly assigned, 3 each, to all combinations of 4 operators and 3 machines. The results are shown in the table below.
Machine I Machine II Machine III
Operator A 115 111 109
115 108 110
119 114 107
Operator B 117 105 110
114 102 113
114 106 114
Operator C 109 100 103
110 103 102
106 101 105
Operator D 112 105 108
115 107 111
111 107 110
At 0.05 level of significance test whether or not there
a. Is an interaction between operators and machines?
b. Is there an effect due to operator?
c. Is there an effect due to machine?
d. Plot the mean breaking strength for each operator for each machine.
e. If appropriate, use the Tukey procedure to examine differences among operators and among machines.
f. What can you conclude about the effects of operators and machines on breaking strength? Explain.