Types Of Tree Diagrams

Total quality management is the philosophy of management for continuous improvement in term of quality in the process and the products. To implement the total quality management, it have several tool that can be used by the person who want to implement the total quality management. One of the tool is tree diagram.

The definition of tree diagram is the graphical or diagram tool that systematically break down, and then mapped in detail in growing, all components or elements of the situation, phenomenon, process, or condition at the stage of succession. It also used when to make the calculations of probabilities and to make the decision. By using tree diagram also, the description of the problem can be seen in more clearly.

Tree diagram know as systematic diagram, analytical tree, hierarchy diagram and tree analysis. It called systematic diagram because of the systematically map all the details related to a problem or project. That way it helps to achieve the ultimate goal and every goal related sub-issues under study. This is also called ‘Dendrogram’ as the word ‘dendro’ in Greek mean tree.

The tree diagram starts with a node or item is divided into two or more branches, then each branch will be divide into two or more. With the branches of the tree it will look like a tree. That’s why it’s called a tree diagram. It is used to break down the big categories or problem into the smaller categories/problem with a more detailed level. By making a tree diagram, it helps us to think thoughts of a move to a move from general to more specific.

Type of tree diagram

Tree diagram have several different types. The types are :

• Cause and effect tree diagram
• Y to x tree diagram
• Functional tree diagram
• Abstraction tree diagram

Each of the tree diagram has a core and strength which can be surprisingly challenging to capture when a project team tried to build one or more of them. Diagrams have enough similarities in the required data and building process that the team can tangle them up a little potentially dulling results. The table below outlines each type of tree diagram, providing information which helps differentiate the trees by style and function.

Cause-and-Effect

Tree Diagram

Y-to-x

Tree Diagram

Functional

Tree Diagram

Abstraction

Tree Diagram

Application

Uncover root causes that are actionable – to change the problematic effect.

Identify and classify factors (independent variables) that may drive an important results variable.

Identifiy general and specific functionality that operates inconcert in a product or process. The tree structure helps check for completeness and reports the analysis in ways that can hide or expose details appropriate to different audiences.

Distill fragments of data to find messages and themes that are not evident in raw data by itself. Tree powerfully and succinctly reports the insights derived by the team constructing it.

Starting Point

A documented effect

A results measure (dependent variable)

One or more functions delivered by a product or process

Facts that answer a theme question

Construction

Top Down: Starting with the effect, asking why in a nested and branching pattern to surface fundamental causes.

Top Down: Asking the question, “What factors may drive changes in the measure at the current node?”

From Top, Middle or Bottom: Organizing a group of connected functions from the general view to the detailed view.

Bottom Up: Understanding and grouping factual answers to a theme question using rules of abstraction. Discovering and reporting themes that may have been evident in raw data.

Node Wording

Describes factual situations without ambiguity

Describes factors (variables) that can change value

Uses positive, active verbs to describe the node’s functionality

Uses factual report language, free of judgment, emotion or inference

Cause-and-Effect Tree Diagrams

Cause and effect diagram is easy and effective. But sometimes when we have a lot of causes, when a deeper analysis is required for each source individually, the best way to manage by making as tree diagram.

Figure 3: Another Pitfall – Branches That Do Not Answer the “Why”

Example of Cause and Effect Tree Diagram

Y-to-x Tree Diagram

A Y-to-x tree diagram starts with an important decision step (Y) and ask the question, “What are the factors drive this Y?” Although it is not really different from the question of cause and effect, the thrust and content of this tree diagram wants to be distinctly different. Each node in the tree diagram must describe steps or factors that can take different values​​. Factors that could describe the steps that is diversified in continuous (such as time and capacity) for category (such as small, medium and large) but they all have to explain the steps.

Although the spirit of inquiry is the same in each of these cases, by raising questions about the driving factors, the Y-to-x tree diagram interpreting to different languages ​​in the node label, and it led to a different types of a lower level outcome or results, with x identified. Each node should define steps that factors which can take different values

Figure 5: Section of Y-to-x Flowdown Tree for a Medical Device

Example of Y-to-x tree diagram

Functional Tree Diagrams

It can be used to develop administrative functions. In this tree diagram type, it can be split as follows :-

Target circumstances to work in every department

Describe the purpose of the work.

This will bring on the findings a new approach for work, facilitating the improvement and ultimately achieve departmental objectives. This will help to improve administrative structure of itself. Functional tree diagram also used as an engineering method dates back, with verbs are always be used to accurately describe the function. More recently, object-oriented mindset has developed “use cases” that extend the use of (still focused on verb) to the software and business systems.

Example of Functional Tree Diagram

A functional tree diagram it is easier to read and study if every node label focusing on the positive, active verb (such as “measured,” “gathering” or “read”). If a team slipped into the label describing the steps or where or how the function occurs, leaders need to pull the team back to the easier verb discipline.

Abstraction Tree Diagrams (KJ or Affinity)

A KJ (language of processing tool named after its creator, namely Jiro Kawakita) or properly performed affinity diagram to organize the facts in a hierarchy like a tree. Unique among other trees tools that are considered here because they are built from the bottom to the top, abstraction rules apply KJ discover and articulate key messages on the tree diagram. Some of the concepts or themes that may distill meaning is not immediately obvious when looking at the facts much lower.

Figure 8: Section of KJ Diagram (Abstraction Tree)

Example Abstraction Tree Diagram

. When to Use a Tree Diagram

When assigned tasks instead of tasks we always do and requires a thorough understanding of or attention and careful planning before we do.

When problems or things to be resolved is in a large scope and we need to solve in detail and in-depth such as in producing a new product or concept to achieve the aims and objectives.

When developing the solution or an action to conduct other plans.

When reviewing and related analysis process in-depth and detail.

When want to find the causes and the solution to a problem or error.

When assessing or examining issues related to the Implementation of some or all of which maybe can be the solution to the problem.

After the affinity diagram or relationship diagram has been successful in identifying significant issues or cause problems.

As a tool to be used during the presentation in detail and depth to others.

Tree Diagram Procedure

Make or create goals, vision or planning projects or whatever is being studied or research. List and write at the top of the list and write (for vertical tree diagram) or far off of the work surface (for horizontal tree diagram).

Ask a question that will lead you to the next level of detail. For example:

For a goal, action plan or work breakdown structure: “What tasks must be done to accomplish this?” or “How can this be accomplished?”

For root-cause analysis: “What causes this?” or “Why does this happen?”

For gozinto chart: “What are the components?” (Gozinto literally comes from the phrase “What goes into it?”

Brainstorm all possible answers. If an affinity diagram or relationship diagram has been done previously, ideas may be taken from there. Write each idea in a line below (for a vertical tree) or to the right of (for a horizontal tree) the first statement. Show links between the tiers with arrows.

Do a “necessary and sufficient” check. Are all the items at this level necessary for the one on the level above? If all the items at this level were present or accomplished, would they be sufficient for the one on the level above?

Each of the new idea statements now becomes the subject: a goal, objective or problem statement. For each one, ask the question again to uncover the next level of detail. Create another tier of statements and show the relationships to the previous tier of ideas with arrows. Do a “necessary and sufficient check” for each set of items.

Continue to turn each new idea into a subject statement and ask the question. Do not stop until you reach fundamental elements: specific actions that can be carried out, components that are not divisible, root causes.

Do a “necessary and sufficient” check of the entire diagram. Are all the items necessary for the objective? If all the items were present or accomplished, would they be sufficient for the objective?

Tree Diagram Example

The Pearl River, NY School District, a 2001 recipient of the Malcolm Baldrige National Quality Award, uses a tree diagram to communicate how district-wide goals are translated into sub-goals and individual projects. They call this connected approach “The Golden Thread.”

The district has three fundamental goals. The first, to improve academic performance, is partly shown in the figure below. District leaders have identified two strategic objectives that, when accomplished, will lead to improved academic performance: academic achievement and college admissions.

Tree Diagram Example

Tree Diagram Example

Lag indicators are long-term and results-oriented. The lag indicator for academic achievement is Regents’ diploma rate: the percent of students receiving a state diploma by passing eight Regents’ exams.

Lead indicators are short-term and process-oriented. Starting in 2000, the lead indicator for the Regents’ diploma rate was performance on new fourth and eighth grade state tests.

Finally, annual projects are defined, based on cause-and-effect analysis, that will improve performance. In 2000-2001, four projects were accomplished to improve academic achievement. Thus this tree diagram is an interlocking series of goals and indicators, tracing the causes of systemwide academic performance first through high school diploma rates, then through lower grade performance, and back to specific improvement projects.

Excerpted from Nancy R. Tague’s The Quality Toolbox, Second Edition, ASQ Quality Press, 2004, pages 501-504.

A tree diagram is an illustration which generally displays all possible outcomes from one root event or how all of its components are related to one another. When thinking in terms of genealogy, a tree diagram would ideally start with one couple, then branch to their children, then on to their grandchildren and so on. In terms of science or mathematics, these diagrams show all possible results which may stem from one compound or event. Even in subjects like history or English, a tree diagram may be used to show how events or ideas connect to one another.

Using a tree diagram in subjects like history may display events and related outcomes in a way in which students understand and remember easier. It is said that 60 percent of the population are visual learners, so diagrams such as these may not only help the individual students, but also aid in overall classroom performance. Other subjects like science and math may use this type of diagram for much the same reason, but diagrams in these subjects tend to show possibilities as well as relationships.

The tree diagram may be used in many industries as well. Companies might create a decision diagram to explore the likely benefits and disadvantages of financial ventures before taking any risk. They can outline future paths to reach certain goals easily as well. Medical professionals sometimes create a tree diagram to explain a certain group’s risk of disease based on lifestyles, genetics, and other factors. Genetic engineers can even use these diagrams to predict the outcomes of different couplings within the plant, animal, and even human kingdoms.

There are even software programs available which create tree diagrams for different purposes. The user may put in a stem occurrence and the number of results he or she wants the program to return. Then the program can quickly analyze the potentialities and build a tree diagram from them. Some programs can even calculate and display the likelihood of each result, such as whether it’s more likely a couple will have a blue-eyed child or a brown-eyed one.

A tree diagram shows how the elements in it are related or how one action or event might end. They are considered a safe way to assess risk and may even be used as a teaching tool. They are most effective when used as a general guideline, as they generally cannot allow for unforeseen variables.