Discussion:
Q: A quality control engineer wants to compare the production process of parts manufactured by four different companies. The engineer randomly samples a total of 270 parts from the four companies and summarizes the results in the following table. Based upon the results of the sample, can the quality control engineer conclude that part quality and manufacturer are independent at level of significance of 1%
Observed Data "O"
|
Part Quality
|
Co. A
|
Co. B
|
Co. C
|
Co. D
|
Row Total
|
|
Defective
|
8
|
8
|
10
|
9
|
|
|
Non-Defective
|
60
|
65
|
60
|
50
|
|
|
Column Total
|
|
|
|
|
|
a) Formulate the hypothesis
b) State the decision rule
c) Calculate Chi-Square statistic
Determine the conclusion and answer the question