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4
Hypothesis Testing for Quality Control
at a Manufacturing Company
The process engineer at a manufacturing company decides to perform qual-
ity control checks with respect to (1) proportion of defectives for the popu-
lation of a particular category of products, (2) performance of a particular
machine, and (3) comparison of output from three different shifts.
Section 4.1 gives a brief description of the dene phase. Section 4.2
illustrates the measure and analyze phases with detailed instructions for
using Minitab
®
. The improve and control phases are briey described in
Section 4.3.
4.1 Define Phase
The process engineer has the following hypothesi ...