Tree diagram in advanced quality tools
What is a Tree diagram?
A tree diagram is a tool used to find out the way and the tasks that need to be done to achieve a primary goal and related sub-goals. A tree diagram is to find out the best and most effective way of achieving the goal. The tree diagram is a hierarchical graphic representation of the steps required to achieve a goal.
A tree diagram starts with one item and then divide into two or more branches and further these branch into two or more & so on. It is used to break down a broad category into smaller categories. The tree diagram helps us to move step by step from general to specific things. This is a generic tool that can be used for a variety of purposes.
Types of tree diagram
The tree diagram can be of two types:
- First is a diagram that breaks down the main subject into basic elements and shows their relationship to the goal and means to achieve the goal.
- The second is to show the means and process necessary to successfully implement the given plan.
When to use the tree diagram?
A tree diagram is used for many purposes as below:
- When analyzing the processes in detail
- While trying to find out the root cause of a problem
- While trying to implement remedial action
- For analyzing key issues identified by the affinity diagram and Relation diagram.
- When a problem is addressed in general terms and needs to move to a specific one to take action.
- It is an easy way to explain the detail
How to create a tree diagram?
Below are the steps to make a tree diagram:
- Identify the problem with a clear statement and display it.
- Do brainstorming to find out the means to achieve the goals. That can be primary, secondary, 3rd mean, 4th means and so on.
- Ask a question, which will lead to the next level of details such as, What tasks must be done to achieve this? What causes this? Why does this happen? etc
- Carry out the necessary and sufficient checks. It is similar to checking the logical validity of the causes used in the cause-and-effect diagram.
- Continue to identify each new idea in a subject statement. Do not stop until you reach basic elements such as Specific action that can be taken and the root cause of the problem.
Benefits of a tree diagram
The benefits of a tree diagram are:
- As the approach is systematic and logical, there is no chance that any essential item will be omitted.
- It identifies and displays the strategies for solving the problem easily and so effectively that team members are agreed with each other.
Tree diagram example
A Hotel manager wants to improve the satisfaction level of his customer. A brainstorming session was done to identify the various factors improving customer satisfaction. These factors were grouped and converted into a tree diagram as below:
By identifying the factors influencing customer satisfaction, data was collected on a regular basis and required necessary actions are taken on the factors affecting customer satisfaction.