Quality Analytics

What is quality?

Meeting or exceeding customers expectations.

Garvin’s 8 Dimensions of Product Quality:

1) Performance - operating characteristics - how fast does a car go? mpg? 2) Functionality - supplemental attributes - not necessary, but nice. Movies on a plane, stereo/gps in car 3) Durability - how long does it last - 4) Reliability - will this product work when you want it to - will your car start on a cold day 5) Conformance - does it reach specs? - is the gas at the right octane? 6) Serviceability - how easy is it to maintain and service a product - 7) Aesthetics - how does it look? - is it sexy? is it alluring? 8) Perceived Quality - does the customer think it is nice? - Company reputation. “I’m a Ford guy”

Other Quality
  • Consistancy: If I go to other locations or if I go to multiple times, or on different days of the week, are they the same. Think McDonald’s. Has to be the same everywhere.
  • Courtesy: Think Chick-Fil-A’s “My Pleasure”
  • Convenience/Availability: Think banks not being available outside 8-4.
  • Communication: Is the customer kept up to date?
  • Timeliness: Can you be fast to my needs? Are you quick?
  • Trustworthiness: Can I trust you? do you bill me for only the right things?
  • Security: Do I feel safe? Do I feel risks?

Costs of Quality:

Appraisal Costs

Making sure every part is working the same

  • Inspection
  • Lab
  • Calibration
  • Audits

Prevention Costs

Preventing defects from occuing

  • Training
  • Quality Improvements
  • Quality Department

Internal Failure Costs

  • Scrap
  • Rework
  • Retesting

External Failure Costs

  • Warranty
  • Reputation
  • Returns
  • Litigation


How much a thing varies.

A measure of change in a variable.

Differences between items.


  • Random Causes
    • Inherent in the process
    • Unavoidable
  • Special Causes
    • Can be identified
    • Can be corrected

Variation in terms of random causes can be attributed to a normal distribution.

Control Charts