In the last InsideSixSigma issue, we published a brain teaser by Steve Wise, who proposed a scenario and asked you to pick a chart that best described the situation in a manufacturing operation. Here, Wise gives the correct response and comments on the wrong ones.

Correct response
The correct answer is E. Using a group chart of residuals (plots of maximun and minimum differences between the expected temperature and the actual temperature at each key temperature), one can track the output of all key temperature readings from a given cycle in the same group plot point.

Incorrect Responses

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