Ishikawa fishbone diagram

Cause and Effect Analysis Cause and Effect Analysis is a technique for identifying all the possible causes (inputs) associated with a particular problem / effect (output) before narrowing down to the small number of main, root causes which need to be addressed.

Cause and Effect Analysis is a valuable tool for: Focusing on causes not symptoms capturing the collective knowledge and experience of a group Providing a picture of why an effect is happening Establishing a sound basis for further data gathering and action Cause and Effect Analysis can also be used to identify all of the areas that need to be tackled to generate a positive effect.

Ishikawa diagram A Cause and Effect diagram (also known as a Fishbone or Ishikawa diagram) graphically illustrates the results of the analysis and is constructed in steps. Cause and Effect Analysis is usually carried out by a group who all have experience and knowledge of the cause to be analyzed. Cause-and-Effect diagrams graphically display potential causes of a problem

Introduction (FBD= fishbone diagram) FDB is a tool to find out relationships: Use in QM especially in automotive industry On of the tool set used to create so called 8D report (8 disciplines=FBD+5WHYs+PA+QM) Another tool : 5 WHYs – will be cleared later Another tool : PARETO=PA analysis will be shown later Cause Effect

1. Identify the Problem/Issue Select a particular problem, issue or effect. Make sure the problem is specific, tightly defined and relatively small in scope and that everyone participating understands exactly what is being analyzed. Write the problem definition at the top of the flip chart or whiteboard.

2. Brainstorm Conduct a Brainstorm of all the possible causes of the effect, i.e., problem. Have a mixed team from different parts of the process (e.g., assemblers and testers). Get a “fresh pair of eyes” - from someone who is not too close to the process. Have a facilitator - an impartial referee. Everyone is an equal contributor (“leave stripes at the door”). Fast and furious - go for quantity rather than quality (of ideas) at first. Involve everyone, or question why he/she is here. Timing - set an upper limit and best time/day of the week. Offer an incentive (free lunch?). Know when to stop. Recognize that this is a snapshot of how the group thinks today. Re-visit the problem again. Refer also to the Process Mapping tool. Consider (how) should you involve your customer?

2. Brainstorm (continued) Write each idea on a Post-It® to make it easy to transfer them onto the fishbone diagram later. Be careful not to muddle causes and solutions at this stage. It is important to brainstorm before identifying cause categories otherwise you can constrain the range of ideas. However, if ideas are slow in coming use questions such as, ‘what about?’, to prompt thoughts.

Fishbone diagram Mother Nature Men Salary To hot Training Terrible cold Dissatisfied worker Incapable Dangerous Treacherous Obsolete Management Machines (Methods, Material, Manpower, Measurement, Machines, Mother Nature,Management)

4. Align Outputs with Cause Categories Review your brainstorm outputs and align with the recommended major cause categories, e.g., the People, Method, Machine, Material, Environment and Measurement System. Note: These may not fit every situation and different major categories might well be appropriate in some instances, however, the total should not exceed six. Other categories may include Communications, Policies, Customer/Supplier Issues etc.

5. Allocate Causes Transfer the potential causes from the brainstorm to the diagram, placing each cause under the appropriate category. If causes seem to fit more than one category then it is acceptable to duplicate them. However, if this happens repeatedly it may be a clue that the categories are wrong and you should go back to step 4. Related causes are plotted as ‘twigs’ on the branches. Branches and twigs can be further developed by asking questions such as ‘what?’, ‘why?’ ‘how?’, ‘where?’ This avoids using broad statements that may in themselves be effects. Beware, however, of digging in and getting into bigger issues that are completely beyond the influence of the team.

6. Analyze for Root Causes Consider which are the most likely root causes of the effect. This can be done in several ways: Through open discussion among participants, sharing views and experiences. This can be speeded up by using Consensus Decision Making. By looking for repeated causes or number of causes related to a particular category. By data gathering using Check Sheets, Process Maps, or customer surveys to test relative strengths through Pareto Analysis. Once a relatively small number of main causes have been agreed upon, Paired Comparisons, can be used to narrow down further. Some groups find it helpful to consider only those causes they can influence.

Fishbone diagram-support heart of the problem Mother Nature Men Low salary HR have a bad recruitment policy Bad training Bad weather Good weather Lower quality of the consultants Consultant takes holiday Phlegmatic person reacts later than expected Consultant is on sick leave Dissatisfied customer Incapable Bad communication Interest in golf only Bad SW for support (HELP DESK) Management Machines (Methods, Material, Manpower, Measurement, Machines)

Dissatisfied employee I

Dissatisfied employee II

5WHYs WHY 1 :Why my car had stopped ? No petrol in tank WHY 2 :Why i did not have a petrol in my tank ? I did not buy in the morning on my way to work WHY 3 :Why i did not buy a petrol ? No money in my pockets WHY 4 : Why no money i my pockets? Evening poker WHY 5 : Why i did not win a poker game? I do not know how to bluff!

5WHYs Cause Effect

Pareto analysis I

Pareto analysis II - data Frequency Freq (%) Freq accum(%) Difficulty Resignation Underestimation Low motivation 6 - (35,29 )- (35,29) 5 - ( 29,41 )- (64,71) 4 - ( 23,53 )- (88,24) 2 - ( 11,76 )- (100,00)

Pareto analysis III

Vilfredo Pareto in person…