For which of the following should we use an X-bar chart based on sample means to monitor process quality?
A) Grades in a freshman "pass/fail" course
B) Tire pressures in an auto assembly plant
C) Vehicles passing emissions inspection
D) Computer software errors
E) Number of units with missing operations

Question

Quizplus · Accepted Answer

An X-bar chart based on sample means is appropriate for continuously measured variables, such as tire pressures in an auto assembly plant. It is not appropriate for discrete data, such as pass/fail grades, or count data, such as number of units with missing operations. It is also not appropriate for categorical data, such as vehicles passing emissions inspection. Computer software errors can be counted, but an individuals chart may be more appropriate for monitoring the process.

For Which of the Following Should We Use an X-Bar