Assignable cause

Decision Type:

Method Category:

Categories: Terms

A name for the source of variation in a process that is not due to chance and therefore can be identified and eliminated.

Synonyms:

special cause

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Using Statistical Process Control in Environmental Root Cause Analysis
Making sure statistical process control is established before finalizing mitigation avoids a second crisis during implementation.
SPC Assumptions
SPC Average and Range Charts

In-Control State
A process that exhibits only random, common cause variation (as opposed to chaotic, assignable, or special cause variation). A process operating with only random variation is statistically stable.

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About Fred Schenkelberg

I am the reliability expert at FMS Reliability, a reliability engineering and management consulting firm I founded in 2004. I left Hewlett Packard (HP)’s Reliability Team, where I helped create a culture of reliability across the corporation, to assist other organizations.

About Fred Schenkelberg

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