Lean Manufacturing and Six Sigma Definitions

Glossary terms, history, people and definitions about Lean and Six Sigma

Fishbone Diagram

Also known as a Cause and Effect diagram, or Ishikawa diagram. The method was created by Kaoru Ishikawa in the 1960’s. He created it to help employees avoid solutions that merely address the symptoms of a much larger problem.

The defect or problem is shown as the fish’s head on the right side (typically). The major categories or causes of the problem or defect are the ribs off the fish’s backbone.

Ishikawa Fishbone Diagram

The most common categories are the 6 M’s:

  • Manpower (People)
  • Methods (Processes/Procedures)
  • Materials (Supplies/Vendors)
  • Machines (Equipment)
  • Measurement
  • Mother Nature (Environment)

Another concept is 4 P’s:

  • Policies
  • Procedures
  • People
  • Plant/Technology

From each rib, additional levels or root causes of each category become branches from the bones.

Links

Videos

 

Synonyms:
Cause and Effect Diagram, C&E diagram