In this paper we describe several methods for providing benchmark estimate of the potential width capability of a process when the process becomes stable in the statistical process control (SPC) sense of the word. We define continually meet customer requirements which are expressed in terms of product specifications. Product specifications are generally concerned with both the center and the width of the various characteristics of the process output. The term "capability" is appropriate for process sense. Should the process not be in control, the term "process capability" (Cp) should be replaced by "process performance" (Pp); and the ratio calculations should be based on the capability standard deviation and the performance standard deviation respectively. This point is describes several methods for evaluating the capability standard deviation which do not require the use of control charts. A numerical example is given.

Date of creation, presentation, or exhibit



The 2004 Northeast Decision Sciences Institute Annual Meeting Proceedings, Atlantic City, NJ -- “Estimating Potential Capability of an Unstable Process”, with D. S. Holmes, 290-292, March, 2004 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type

Conference Proceeding

Department, Program, or Center

Accounting (SCB)


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