WHAT IS A FISHBONE DIAGRAM?

Introduction to FishBone Diagram

The fishbone diagram is a graphical representation used by organizations to find the causes of a problem or an effect. This effect can be either a negative or positive one. The Fishbone diagram is also called as either “Ishikawa diagram” or “cause-and-effect diagram”. Its appearance resembles that of a fish skeleton, allowing the listing of factors that may affect a problem or desired outcome of some activity. The head of the fishbone diagram is the problem that is under the scope of analysis. The bones of the diagram represent causes of the problem. Every cause within diagram can be further developed by its own causes.

Fishbone diagrams are an ideal Six Sigma tool to help people find the root of a complicated problem. Once you are able to learn what is causing a problem, it can help you determine ways you can fix it. Fishbone diagrams may be used entrepreneurs and almost any organization or individuals that has a problem. Fishbone diagrams are frequently used within the Six Sigma methodology because they present accurate depictions of cause and effect drawn out on paper.

One of the advantages of using fishbone diagrams is the ability they give business owners to analyze the root causes of factors that occur in many different aspects of business operations. This makes it easier to find solutions more quickly. If the root cause is known, a solution can be more clearly seen. Another benefit of using fishbone diagrams and Six Sigma is the fact that it is a graphical representation and can be seen (not abstract). If team members are able to see the actual effects of a particular process, they will be better equipped with the tools necessary to make improvements. Both negative and positive results can then be analyzed and important decisions reached more easily.

When designing the fishbone graph, employees and managers should not start pointing fingers at each other. Blaming another person for a particular problem will not solve the problem but will, in fact, waste time and cause employee dissent. To find solutions to organizational problems, managers have to brainstorm along with employees in a teamwork environment.

Advantages of FishBone Diagram

1. Highly corresponding tool which may spark more samples of root causes
2. Quickly establish if the basis cause is found multiple times within the same or totally different causative tree
3. Allows one to check all causes at the same time
4. Good visualisation for presenting problems to stakeholders

Disadvantages of FishBone Diagram

1. Complex defects would possibly yield loads of causes which could become visually cluttering
2. Interrelationships between causes don’t seem to be simply identifiable

Procedure for FishBone Diagram

1. Agree on a tangle statement (effect). Write it at the middle right of the flipchart or whiteboard. Draw a box around it and draw a horizontal arrow running to that.
2. Brainstorm the foremost classes of causes of the problem. If this is often tough to use generic headings:
   • Methods
   • People (Manpower)
   • Machines (Equipment)
   • Measurement
   • Materials
   • Environment
3. Write the classes of causes as branches from the main arrow.
4. Brainstorm all the doable causes of the issue. Raise the question “Why will this happen?” As every plan is given, the assistant writes it as a branch from the appropriate category. Causes are written in many places if they relate to many classes.
5. Again raise the question “Why will this happen?” regarding every cause. Write sub-causes branching off the causes. Continue to raise the question “Why?” and generate deeper levels of causes. Layers of branches indicate causative relationships.
6. When the group runs out of ideas, focus attention to places on the chart wherever ideas are few.

How to Use the FishBone Diagram?

Steps to use the FishBone Diagram :

1. Identify the Problem

First, write down the precise drawback you face. wherever applicable, identify who is involved, what the matter is, and when and where it happens. Then, write the issue in a box on the left-hand sideof an outsized sheet of paper, and draw a line across the paper horizontally from the box. This arrangement, looking just like the head and spine of a fish, provides you space to develop ideas.

Example:

A manager is having issues with an uncooperative branch office.

         Figure 1 – Cause and Effect Analysis Example Step 1

2. Solve the Major Factors Involved

Identify the factors that may be part of the issues. It may be systems, equipment, materials, external forces, people involved with the problem, etc.

Try to identify as many of these as possible. 

Brainstorm  any other factors that may affect the situation. Then draw a “spine”  line of the diagram for each factor, and label each line. 

Example:

• Site.
• People.
• Equipment.
• Task.
• Control.

3. Identify Possible Causes:

Now, for every factors you thought-about in step two (solve the major factors involved), brainstorm doable causes of the issue which will be associated with the factor.
Show these doable causes as shorter lines coming back off the “bones” of the diagram. wherever a cause is massive or advanced, then it’s going to be best to interrupt it down into sub-causes. Show these as lines coming back off every cause line.

Example:

For each of the factors recognized in step 2, the manager brainstorms possible causes of the problem, and adds these to the diagram, as shown in figure below.

Figure 3 – Cause and Effect Analysis.

4. Analyze your Diagram:

You should have a diagram showing all the possible causes of the problem.
Depending on the complexity and importance of the problem, you should investigate the causes further. This may involve setting up investigations, carrying out surveys,etc. This will be designed to test which of the possible causes is actually contributing to the issue.

Example:

The manager has completed his analysis. If he had not looked at the problem this way, he might have assumed that people in the branch office were “being difficult.”
Instead he thought that the best approach is to arrange a meeting with the Branch Manager. This would allow him to brief the manager fully and talk through any problems that he/she may be experiencing.

Indented Hierarchy FishBone Diagram

An alternate format for a Cause and effect diagram is that the “indented hierarchy fishbone”. This format is also easier to use in word processing or spreadsheet program. Following is associate degree example of our Free-Throw example using the indented hierarchy method:

Effect – Made (Missed) Free Throws

Cause –

1. Method – Shooting Mechanics
   1. Balance
   2. Bend Knees
   3. Aiming Point
   4. Hand Position
   5. Follow-through
2. Material – Ball
   1. Size of Ball
   2. Air Pressure
   3. Grain/Feel/Grip
   4. Lopsidedness
3. Man – Shooter (Closely related to method in this example)
   1. Concentration
   2. Motivation
   3. Training
      1. Conditioning
      2. Consistency (Muscle Memory)
      3. Adjustment to Other Variables
4. Environment – Weather
   1. Wind Gusts / Sun / Rain
      1. Outside vs. Inside
5. Machine – Hoop and Backboard
   1. Rim Height
   2. Rim Size
   3. Rim “Play” – Rigidity
   4. Rim Alignment
   5. Backboard Stability

FishBone Diagram Example

This diagram was drawn by a manufacturing team to grasp or to understand the source of periodic iron contamination. The team used the six generic headings to prompt concepts. Layers of branches show thorough puzzling over the causes of the issue.

For example, below the heading “Machines,” the concept “materials of construction” shows four sorts of instrumentation and so many specific machine numbers.
Note that some concepts seem in two different places. “Calibration” shows up below “Methods” as an element within the analytical procedure, and conjointly below “Measurement” as a cause of lab error. “Iron tools” are considered a “Methods” drawback once taking samples or a “Manpower” drawback with maintenance personnel.

To learn more about Fishbone diagram or to learn business analysis, check out the Business Analysis Training courses