(a) What is shown on the
(a)
Explain what is shown on the
Answer to Problem 10CR
The
Explanation of Solution
The
(b)
Mention three ways to set the control limits on the
Answer to Problem 10CR
The three ways to set the control limits on the
Explanation of Solution
The control limits for
Control limits with known
If the values of
In the formula,
Empirical control limits:
If the value of
In the formula,
Control limits with R method:
In the formula,
(c)
Explain how the good empirical control limits for the
Answer to Problem 10CR
The good empirical control limits for the
Explanation of Solution
Justification: The three sigma control limits would be very effective for the control charts because these limits would give clear knowledge about the special cause variations in the process. Also, the good empirical control limits can be obtained by when the samples in the process are taken independently than using the same data.
(d)
Explain why quality control samples are sometimes small.
Answer to Problem 10CR
The quality control samples are often small because for normally distributed data samples would be normal based on central limit theorem.
Explanation of Solution
Justification: For a normally distributed sample, the small samples can be used for the mean based on the central limit theorem (if the data is normal then even if sample size is small the sample would be normal). Hence the quality control samples are often small.
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Chapter 17 Solutions
Applied Statistics in Business and Economics
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