Welcome, Guest
Do you need customer support or technical assistance? Click here to submit a support ticket...

TOPIC: Control limits.

Control limits. 7 years 1 month ago #800

  • Chan Krish
  • Chan Krish's Avatar
  • Offline
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
Hello Everyone,

I found the following definition of Control limits in the PMBOK glossary.

"The area composed of three standard deviations on either side of the centerline, or mean, of a normal distribution of data plotted on a control chart that reflects the expected variation in the data."

What does the three standard deviations denote? The two control limits UCL and LCL are shown in the control chart diagram. What is the third SD mentioned here?

Re:Control limits. 7 years 1 month ago #804

  • Cornelius Fichtner
  • Cornelius Fichtner's Avatar
  • Offline
  • Administrator
  • PrepCast Instructor
  • Posts: 981
  • Thank you received: 157
  • Karma: 30
Chan,

Please watch episode E08.04 Advanced Quality Management Tools where we discuss these control limits. And the standard deviation is explained in E08.00 Project Quality Management Overview
Until Next Time,
Cornelius Fichtner, PMP, CSM
President, OSP International LLC

Re:Control limits. 7 years 1 month ago #810

  • Chan Krish
  • Chan Krish's Avatar
  • Offline
  • Fresh Boarder
  • Posts: 9
  • Karma: 0
LCL and UCL basically represents the -3 sigma and +3 sigma respectively. The PMBOK phrase seemed to denote 3 different SD measurements, but it was indeed referring to the 3times sigma value on both sides of mean.

Thanks for the clarifications!
Moderators: Yolanda Mabutas, Ahmed Amin, Scott Gillard, Michael DeCicco, Rahul Kakkar, Fernando Jr Sinlao Lim, Mary Kathrine Padua, Chris Preziotti, Lazard Toe, ITBMC, MPM, CIPM, PMP, ITIL, Christian Winter, Kevin Nason, Michael Sumaquial, PMP, Mark Wuenscher, PMP

OSP INTERNATIONAL LLC
OSP INTERNATIONAL LLC
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®