Cause and Effect Diagram
A problem-solving tool that graphically illustrates the relationship(s) between various process elements which prepares problem solvers to assess the impact of variation from standard.
Example: If “widget” production is charted on 3 similar machines and two machines produce equal amounts of “widgets” per hour while one machine produces 20% fewer parts per hour (as per drawn or charted data) then a variable exists that is “causing” the poorer performance of the third machine.
Since the best “widget” producing machines run on electricity and regulated air pressure these variables could be having a negative impact on production. Diagramming each element will show (perhaps) that machine #3 was running at 80 p.s.i. instead of 120 p.s.i. like the other two machines.