{domain:"www.qualitydigest.com",server:"169.47.211.87"} Skip to main content

User account menu
Main navigation
  • Topics
    • Customer Care
    • FDA Compliance
    • Healthcare
    • Innovation
    • Lean
    • Management
    • Metrology
    • Operations
    • Risk Management
    • Six Sigma
    • Standards
    • Statistics
    • Supply Chain
    • Sustainability
    • Training
  • Videos/Webinars
    • All videos
    • Product Demos
    • Webinars
  • Advertise
    • Advertise
    • Submit B2B Press Release
    • Write for us
  • Metrology Hub
  • Training
  • Subscribe
  • Log in
Mobile Menu
  • Home
  • Topics
    • 3D Metrology-CMSC
    • Customer Care
    • FDA Compliance
    • Healthcare
    • Innovation
    • Lean
    • Management
    • Metrology
    • Operations
    • Risk Management
    • Six Sigma
    • Standards
    • Statistics
    • Supply Chain
    • Sustainability
    • Training
  • Login / Subscribe
  • More...
    • All Features
    • All News
    • All Videos
    • Contact
    • Training

Gauging Gage, Part 1

How accurately can you assess your measurement system with 10 parts?

Joel Smith
Tue, 05/09/2017 - 12:02
  • Comment
  • RSS

Social Sharing block

  • Print
  • Add new comment
Body

‘You take 10 parts and have three operators measure each two times.”

ADVERTISEMENT

This standard approach to a gage repeatability and reproducibility (GR&R) experiment is so common, so accepted, so ubiquitous, that few people ever question whether it is effective. Obviously, one could look at whether three is an adequate number of operators or two an adequate number of replicates, but in this first of a series of posts about “gauging gage,” I want to look at 10. Just 10 parts. How accurately can you assess your measurement system with 10 parts?

Assessing a measurement system with 10 parts

I’m going to use a simple scenario as an example. I’m going to simulate the results of 1,000 GR&R studies with the following underlying characteristics:
1. There are no operator-to-operator differences, and no operator/part interaction.
2. The measurement system variance and part-to-part variance used would result in a %Contribution of 5.88 percent, between the popular guidelines of <1% being excellent and >9% being poor.

 …

Want to continue?
Log in or create a FREE account.
Enter your username or email address
Enter the password that accompanies your username.
By logging in you agree to receive communication from Quality Digest. Privacy Policy.
Create a FREE account
Forgot My Password

Comments

Submitted by gej on Wed, 05/10/2017 - 02:10

GRR

Whether you measure 5, 10 or 10,000 parts you are already inferring that the data set is homogenous when you go on to calculate the summary statistics to estimate the process parameters. The first task is to construct a control chart to understand whether you have homogeniety in the data set.

If you dont have homogeniety you will need to deal with it there before you even contemplate moving forward because any statistics you compute will be meaningless. 

  • Reply

Add new comment

Image CAPTCHA
Enter the characters shown in the image.
Please login to comment.
      

© 2025 Quality Digest. Copyright on content held by Quality Digest or by individual authors. Contact Quality Digest for reprint information.
“Quality Digest" is a trademark owned by Quality Circle Institute Inc.

footer
  • Home
  • Print QD: 1995-2008
  • Print QD: 2008-2009
  • Videos
  • Privacy Policy
  • Write for us
footer second menu
  • Subscribe to Quality Digest
  • About Us
  • Contact Us