Ugh, your process is producing some parts that don’t meet your customer’s specifications. Fortunately, after a little hard work, you find a way to improve the process.

However, you want to perform the appropriate statistical analysis to back up your findings and make it easier to explain the process improvements to your boss. And it’s important to remember your boss is not too familiar with statistics, so you’ll have to take it slow and show lots of “visual aids” as part of your explanation. How should you begin?

Enter before-and-after process capability analysis, which evaluates how well a process meets a set of requirements defined by specification limits.

For example, a manufacturer of photocopiers requires that the width of a rubber roller must be between 32.523 cm and 32.527 cm to avoid paper jams. Capability analysis reveals how well the manufacturing process meets these specifications, and provides insight into how to improve the process.

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