The lengths of the bars represent frequency or cost (time or money), and are arranged with longest bars on the left and the shortest to the right.
The graph is accompanied by line graph which shows the cumulative totals of each category.
Graph visually depicts which situations are more significant.
The chart gets its name from the Pareto Principle, which suggests that 80 percent of the trouble comes from 20 percent of the problems.
Why use a Pareto Chart?
Breaks big problem into smaller pieces
Identifies most significant factors
Shows where to focus efforts
Allows better use of limited resources
Example of a Pareto Chart
The below chart shows that 60% of reported causes of late arrivals can be attributed to two factors... traffic and child care, and that 80% of reported causes for late arrivals can be attributed to three factors... traffic, child care, public transportation. This is helpful when a team is trying to decide on which problem causes to address. The Pareto Chart indicates that a team may want to focus on finding solutions to the first two or three causes, which address 80% of the problem. These are the most significant causes and will address the majority of the problem. When to Use
When analyzing data about the frequency of problems or causes in a process.
When there are many problems or causes & you want to focus on the most significant.
When analyzing broad causes by looking at their specific components.
When communicating with others about data.
Constructing a Pareto Chart
1. Record the raw data. List each category and its associated data count.
2. Order the data. Prepare an analysis sheet, putting the categories in order and placing the one with the largest count first.
3. Use Excel to create your chart and plot your data (Column Chart, 1st chart under 2D)
4. Provide a Title, a Legend, and Axis Labels. Give the chart a title that identifies the process you are investigating and compose a legend that tells:
The period of time when the data were collected
The location where the data were collected
The person or team who collected the data
Detailed instructions / practice
Click on attached Word file for details and an example of how to create a Pareto Chart.
Interpreting Pareto Charts
When you look at a Pareto Chart, you can see break points in the heights of the bars which indicate the most important categories. This information is useful when you are establishing priorities. (See example above.)
Additional Resources Here is a link to a wonderful resource on creating Pareto Charts.
Run Charts
A Run Chart is the most basic tool used to display how a process performs over time.
It is a line graph of data points plotted in chronological order—that is, the sequence in which process events occurred. These data points represent measurements, counts, or percentages of process output.
Run Charts are used to assess and achieve process stability by highlighting signals of special causes of variation
Why use a Run Chart?
Using Run Charts can help you determine whether your process is stable (free of special causes), consistent, and predictable.
Unlike other tools, such as Pareto Charts or Histograms, Run Charts display data in the sequence in which they occurred. This enables you to visualize how your process is performing and helps you to detect signals of special causes of variation.
A Run Chart also allows you to present some simple statistics related to the process:
Median: The middle value of the data presented. You will use it as the Centerline on your Run Chart.
Range: The difference between the largest and smallest values in the data. You will use it in constructing the Y-axis of your Run Chart.
Example of a Run Chart
Constructing a Run Chart
1. List data in the sequence in which it occurred
2. Order the data to determine the range. Order the data from the lowest value to the highest value. The range is the difference between the highest and lowest values
3. Calculate the median – once the data have been listed from the lowest to highest value, count off the data points and determine the middle point in the list of measurements… the point that divides the series of data in half
If the count is an odd number, the middle is an odd number with an equal number of point on each side. Example – if you have nine measurements, the median is the fifth value
If the count is an even number, average the two middle measurements to determine the median value. Example – if there are ten measurements, the median is the average of the fifth and sixth values . To determine the average, just add them together and divide by two.
4. Use Excel to create your chart and plot your data (Line chart with Markers)
5. Provide a Title and a Legend. Give the chart a title that identifies the process you are investigating and compose a legend that tells:
The period of time when the data were collected
The location where the data were collected
The person or team who collected the data
Detailed instructions / practiceClick on attached Word file for details and an example of how to create a Run Chart. Interpreting Run Charts Look for trends, runs, or cycles that indicate the presence of special causes.
A Trend signals a special cause when there is a sequence of seven or more data points steadily increasing or decreasing with no change in direction. When a value repeats, the trend stops. When your Run Chart shows seven or more consecutive ascending or descending data points, it is a signal that a special cause may be at work and the trend must be investigated A Run consists of two or more consecutive data points on one side of the centerline. A run that signals a special cause is one that shows nine or more consecutive data points on one side of the centerline. When your Run Chart shows nine or more consecutive data points on one side of the centerline, it is an unusual event and should always be investigated.
A Cycle, or repeating pattern, is the third indication of a possible special cause. A cycle must be interpreted in the context of the process that produced it. A cycle must recur at least eight times before it can be interpreted as a signal of a special cause of variation. Additional Resources Here is a link to a wonderful resource on creating Run Charts.
Flowcharts
Flowcharts are maps or graphical representations of a process. Steps in a process are shown with symbolic shapes, and the flow of the process is indicated with arrows connecting the symbols. Flowcharts are useful for displaying how a process currently functions or could ideally function.
To construct an effective flowchart:
Define the process boundaries with starting and ending points.
Complete the big picture before filling in the details.
Clearly define each step in the process. Be accurate and honest.
Identify time lags and non-value-adding steps.
Circulate the flowchart to other people involved in the process to get their comments.
Flowcharts don't work if they're not accurate or if the team is too far removed from the process itself. Team members should be true participants in the process and feel free to describe what really happens. A thorough flowchart should provide a clear view of how a process works. With a completed flowchart, you can:
Identify time lags and non-value-adding steps.
Identify responsibility for each step.
Brainstorm for problems in the process.
Determine major and minor inputs into the process with a cause & effect diagram.
Choose the most likely trouble spots.
The symbols that are commonly used in Flowcharts have specific meanings and are connected by arrows indicating the flow from one step to another:
Oval. Ovals indicate both the starting point and the ending point of the process steps.
Box. A box represents an individual step or activity in the process.
Diamond. A diamond shows a decision point, such as yes/no or go/no-go. Each path emerging from the diamond must be labeled with one of the possible answers.
Circle. A circle indicates that a particular step is connected to another page or part of the Flowchart. A letter placed in the circle clarifies the continuation.
Triangle. A triangle shows where an in-process measurement occurs.
Example
Online Tools for creating Flowcharts
gliffy.com
smartdraw.com
PowerPoint
Excel
Cause and Effect Diagram
A Cause-and-Effect Diagram is a tool that helps identify, sort, and display possible causes of a specific problem. It displays the relationship between a given outcome and all the factors that influence the outcome. Cause and Effect diagrams are sometimes called a “fishbone diagram” because of the way it looks. Benefits of using a Cause and Effect Diagram • Helps determine the root causes of a problem or quality characteristic using a structured approach.
• Encourages group participation and utilizes group knowledge of the process.
• Uses an orderly, easy-to-read format to diagram cause-and-effect relationships.
• Indicates possible causes of variation in a process.
• Increases knowledge of the process by helping everyone to learn more about the factors at work and how they relate.
• Identifies areas where data should be collected for further study.
Creating a Cause and Effect Diagram
1. Identify and clearly define the EFFECT to be analyzed
2. Draw the “spine” and create the effect box 3. Identify the main CAUSES contributing to the effect being studied. These are the labels for the major branches of your diagram and become categories under which to list the many causes related to those categories.
4. For each major branch, identify other specific factors which may be the CAUSES of the EFFECT. Identify as many causes or factors as possible and attach them as subbranches of the major branches.
5. Identify increasingly more detailed levels of causes and continue organizing them under related causes or categories. You can do this by asking a series of why ?s.
6.Analyze the diagram. Analysis helps you identify causes that warrant further investigation. Since Cause-and-Effect Diagrams identify only possible causes, you may want to use a Pareto Chart to help your team determine the cause to focus on first.
Look at the “balance” of your diagram, checking for comparable levels of detail for most of the categories.
A thick cluster of items in one area may indicate a need for further study.
A main category having only a few specific causes may indicate a need for further identification of causes.
If several major branches have only a few subbranches, you may need to combine them under a single category.
Look for causes that appear repeatedly. These may represent root causes.
Look for what you can measure in each cause so you can quantify the effects of any changes you make.
Most importantly, identify and circle the causes that you can take action on.
Why-Why Diagram
Problem symptoms and problem causes can look very much alike. For example, the cause of a defective product could be identified as a final inspection problem, a process control problem, or a material procurement problem, yet all of these could be symptoms of a management problem. The following process will help identify fundamental problem causes.
1. Identify the undesirable condition that needs to be corrected or the events associated with this condition. 2. Use the “multiple why” process to identify the causes underlying this undesirable condition.
This process is an adaptation of a Japanese quality technique. It consists of continually asking “why is this occurring?” to each explanation and subsequent explanations until a common cause is identified.
3. Continue this “multiple why” process until a fundamental or root cause is apparent.
The why-why diagram is a variation of the fishbone diagram. It moves from left to right, starting with the problem statement. Instead of a backbone (as in the fishbone diagram) it is designed more like a decision tree. Branches are on the right side and ask the question “Why?” (Higgins, 2006)
external image Why-Why-Diagram.jpg
Works Cited
Higgins, J. M. (2006). 101 Creative Problem Solving Techniques. Winter Park: The New Management Publishing Company.
Creating a Why-Why Diagram in Word or PowerPoint Steps:
State the problem on the left side of the paper.
Create a typical decision tree of causes to the right of the problem by asking a succession of “whys” regarding the problem and each of the possible causes.
Continue this process until a sufficient level of detail has been achieved.
Tools:
With Word 2007 or 2010 or PowerPoint 2007/2010, you can use the SmartArt features. Select the Insert tab. In the Illustrations group on the ribbon, select SmartArt. Select Hierarchy in the left column and a horizontal hierarchy in the middle column. Click OK to insert the diagram.
Decision Matrix (Weighted Criteria)
In some situations teams don’t have enough data to help them reach a conclusion on the root cause(s) of the problem. In these situations, teams can use a Decision Matrix to reach consensus on the most likely root cause(s). This tool helps a team compare the leading candidates for the root cause against criteria that the team decides are important for selecting a root cause.
Steps to using a Matrix Diagram (Decision Matrix)
1. Weight each criterion on a scale of 1-9, with “1” indicating a low value and a “9” indicating a high value. Make sure each criterion has a different weight.
Your team’s criteria may change depending on the problem. Some example of criteria include:
Creates exciting quality for the customer
Can be implemented quickly
Create a positive change
Cost is minimal or within budget
Minimal resistance to changing the root cause
2. Rate each possible root cause against each criterion. An example of a rating system the team may use:
9 = Strongly meets the criterion
5 = Moderately meets the criterion
1 = Weakly meets the criterion
Place the team’s ratings in the top-left portion of each “cell” in the matrix
3. Multiply each rating by the weight of the criterion and place this number in the bottom-right portion of each cell.
4. Tally the score and select the root cause with the highest score.
Run Chart
Flowchart
Cause and Effect Diagram
Why Why Diagram
Decision Matrix (Weighted Criteria)
Pareto Charts
Why use a Pareto Chart?
Example of a Pareto Chart
The below chart shows that 60% of reported causes of late arrivals can be attributed to two factors... traffic and child care, and that 80% of reported causes for late arrivals can be attributed to three factors... traffic, child care, public transportation. This is helpful when a team is trying to decide on which problem causes to address. The Pareto Chart indicates that a team may want to focus on finding solutions to the first two or three causes, which address 80% of the problem. These are the most significant causes and will address the majority of the problem.
When to Use
Constructing a Pareto Chart
1. Record the raw data. List each category and its associated data count.
2. Order the data. Prepare an analysis sheet, putting the categories in order and placing the one with the largest count first.
3. Use Excel to create your chart and plot your data (Column Chart, 1st chart under 2D)
4. Provide a Title, a Legend, and Axis Labels. Give the chart a title that identifies the process you are investigating and compose a legend that tells:
Detailed instructions / practice
Click on attached Word file for details and an example of how to create a Pareto Chart.
Interpreting Pareto Charts
When you look at a Pareto Chart, you can see break points in the heights of the bars which indicate the most important categories. This information is useful when you are establishing priorities. (See example above.)
Additional Resources
Here is a link to a wonderful resource on creating Pareto Charts.
Run Charts
Why use a Run Chart?
Example of a Run Chart
Constructing a Run Chart
1. List data in the sequence in which it occurred
2. Order the data to determine the range. Order the data from the lowest value to the highest value. The range is the difference between the highest and lowest values
3. Calculate the median – once the data have been listed from the lowest to highest value, count off the data points and determine the middle point in the list of measurements… the point that divides the series of data in half
4. Use Excel to create your chart and plot your data (Line chart with Markers)
5. Provide a Title and a Legend. Give the chart a title that identifies the process you are investigating and compose a legend that tells:
Detailed instructions / practiceClick on attached Word file for details and an example of how to create a Run Chart.
Interpreting Run Charts
Look for trends, runs, or cycles that indicate the presence of special causes.
A Trend signals a special cause when there is a sequence of seven or more data points steadily increasing or decreasing with no change in direction. When a value repeats, the trend stops. When your Run Chart shows seven or more consecutive ascending or descending data points, it is a signal that a special cause may be at work and the trend must be investigated
A Run consists of two or more consecutive data points on one side of the centerline. A run that signals a special cause is one that shows nine or more consecutive data points on one side of the centerline. When your Run Chart shows nine or more consecutive data points on one side of the centerline, it is an unusual event and should always be investigated.
A Cycle, or repeating pattern, is the third indication of a possible special cause. A cycle must be interpreted in the context of the process that produced it. A cycle must recur at least eight times before it can be interpreted as a signal of a special cause of variation.
Additional Resources
Here is a link to a wonderful resource on creating Run Charts.
Flowcharts
Flowcharts are maps or graphical representations of a process. Steps in a process are shown with symbolic shapes, and the flow of the process is indicated with arrows connecting the symbols. Flowcharts are useful for displaying how a process currently functions or could ideally function.To construct an effective flowchart:
Flowcharts don't work if they're not accurate or if the team is too far removed from the process itself. Team members should be true participants in the process and feel free to describe what really happens. A thorough flowchart should provide a clear view of how a process works. With a completed flowchart, you can:
The symbols that are commonly used in Flowcharts have specific meanings and are connected by arrows indicating the flow from one step to another:
Example
Online Tools for creating Flowcharts
Cause and Effect Diagram
A Cause-and-Effect Diagram is a tool that helps identify, sort, and display possible causes of a specific problem. It displays the relationship between a given outcome and all the factors that influence the outcome. Cause and Effect diagrams are sometimes called a “fishbone diagram” because of the way it looks.Benefits of using a Cause and Effect Diagram
• Helps determine the root causes of a problem or quality characteristic using a structured approach.
• Encourages group participation and utilizes group knowledge of the process.
• Uses an orderly, easy-to-read format to diagram cause-and-effect relationships.
• Indicates possible causes of variation in a process.
• Increases knowledge of the process by helping everyone to learn more about the factors at work and how they relate.
• Identifies areas where data should be collected for further study.
Creating a Cause and Effect Diagram
1. Identify and clearly define the EFFECT to be analyzed
2. Draw the “spine” and create the effect box
3. Identify the main CAUSES contributing to the effect being studied. These are the labels for the major branches of your diagram and become categories under which to list the many causes related to those categories.
4. For each major branch, identify other specific factors which may be the CAUSES of the EFFECT. Identify as many causes or factors as possible and attach them as subbranches of the major branches.
5. Identify increasingly more detailed levels of causes and continue organizing them under related causes or categories. You can do this by asking a series of why ?s.
6.Analyze the diagram. Analysis helps you identify causes that warrant further investigation. Since Cause-and-Effect Diagrams identify only possible causes, you may want to use a Pareto Chart to help your team determine the cause to focus on first.
Why-Why Diagram
Problem symptoms and problem causes can look very much alike. For example, the cause of a defective product could be identified as a final inspection problem, a process control problem, or a material procurement problem, yet all of these could be symptoms of a management problem. The following process will help identify fundamental problem causes.1. Identify the undesirable condition that needs to be corrected or the events associated with this condition.
2. Use the “multiple why” process to identify the causes underlying this undesirable condition.
- This process is an adaptation of a Japanese quality technique. It consists of continually asking “why is this occurring?” to each explanation and subsequent explanations until a common cause is identified.
3. Continue this “multiple why” process until a fundamental or root cause is apparent.The why-why diagram is a variation of the fishbone diagram. It moves from left to right, starting with the problem statement. Instead of a backbone (as in the fishbone diagram) it is designed more like a decision tree. Branches are on the right side and ask the question “Why?” (Higgins, 2006)
Works Cited
Higgins, J. M. (2006). 101 Creative Problem Solving Techniques. Winter Park: The New Management Publishing Company.
Creating a Why-Why Diagram in Word or PowerPoint
Steps:
Tools:
With Word 2007 or 2010 or PowerPoint 2007/2010, you can use the SmartArt features. Select the Insert tab. In the Illustrations group on the ribbon, select SmartArt. Select Hierarchy in the left column and a horizontal hierarchy in the middle column. Click OK to insert the diagram.
Decision Matrix (Weighted Criteria)
In some situations teams don’t have enough data to help them reach a conclusion on the root cause(s) of the problem. In these situations, teams can use a Decision Matrix to reach consensus on the most likely root cause(s). This tool helps a team compare the leading candidates for the root cause against criteria that the team decides are important for selecting a root cause.Steps to using a Matrix Diagram (Decision Matrix)
1. Weight each criterion on a scale of 1-9, with “1” indicating a low value and a “9” indicating a high value. Make sure each criterion has a different weight.
2. Rate each possible root cause against each criterion. An example of a rating system the team may use:
- 9 = Strongly meets the criterion
- 5 = Moderately meets the criterion
- 1 = Weakly meets the criterion
Place the team’s ratings in the top-left portion of each “cell” in the matrix3. Multiply each rating by the weight of the criterion and place this number in the bottom-right portion of each cell.
4. Tally the score and select the root cause with the highest score.