Problem Solving Tools

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Problem Solving Tools
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What Is A Problem?
A condition or set of circumstances that a person
or group thinks should be changed
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Types of Problems
All Work Is A Process
Defined
Undefined
Stable
Unstable
Improvement
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Definitions
Cause
Effects
Symptoms
Absent
50
40
C
30
H
20
10
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Cause Unknown
Fuzzy Vision
Enlarged Blood Vessel
High Blood Pressure
Obese
Poor Diet
Bad Teeth
Dental Hygiene
Ask Why?
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The Seven QC Tools

• Flowcharts
• Check sheets
• Histograms
• Cause-and-effect diagrams
• Pareto diagrams
• Scatter diagrams
• Control charts

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Flowcharts

• Shows unexpected complexity, problem areas,
  redundancy, unnecessary loops, and where
  simplification may be possible
• Compares and contrasts actual versus ideal flow
  of a process
• Allows a team to reach agreement on process steps
  and identify activities that may impact
  performance
• Serves as a training tool

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Flowcharts

• Why use Flow Charts?
• Used to identify and document the path that a
  product or service follows
• Helps problem solvers understand the process
• Pictorially represents all of the steps of a
  process
• Used to examine the relationship between the
  steps in the process
• Used to compare the existing process with a
  proposed process

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Flowcharts

• Cautions
• Document the process as it truly operates, not as
  it should "ideally" operate
• Include enough detail to address the problem
• Identify departments or operations, not
  individuals

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Check Sheet

• Creates easy-to-understand data
• Builds, with each observation, a clearer picture
  of the facts
• Forces agreement about the definition of each
  condition or event of interest
• Makes patterns in the data become
• obvious quickly

xx xxxxxx x
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Check Sheet

• Why use check sheets?
• Gather data to begin to identify patterns
• Help determine how often certain things occur
• Easy to use on shop floor operations
• Cautions
• Only a beginning in the fact finding process
• Collect data consistently and honestly

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Check Sheets

• Purchase Order Mistakes at Manifold Destiny Plant
  X
• Defect July
  Total
• 5 6
  7 8 9
• No Vendor Info. I II 3
• Missing Charge No. I II I III 7
• Wrong Charge No. III IIII I II 10
• Missing Contact Info. I I I 3
• Missing Part Number III IIII III IIII III 17
• Wrong Part Number II I II I I 7
• No Authorization I 1
• Incorrect Authorization I IIII I I III 11
• TOTAL 12 17 9 9 12 59

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Histogram

• Displays large amounts of data that are difficult
  to interpret in tabular form
• Shows centering, variation, and shape
• Illustrates the underlying distribution of the
  data
• Provides useful information for predicting future
  performance
• Helps to answer the question Is the process
  capable of meeting requirements?

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Histogram

• Why use Histograms?
• Used to display distribution of measurements, or
  the variation in a process
• Shows the spread of the measurements
• Shows how many of each measurement there are
• Cautions
• Use intervals of equal width. Unequal widths are
  confusing
• Keep the histogram simple and to the point. Too
  much information is confusing and visually
  displeasing. The best graphs are easy to
  understand quickly.

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Cause and Effect Diagram

• Enables a team to focus on the content of a
  problem, not on the history of the problem or
  differing personal interests of team members
• Creates a snapshot of collective knowledge and
  consensus of a team builds support for solutions
• Focuses the team on causes, not symptoms

Effect
Cause
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Cause and Effect Diagram

• Why use Cause Effect Diagrams?
• Used to represent the relationship between an
  effect and possible causes influencing it
• Used to determine the root cause of the problem
• Used to identify, explore, and display the
  possible causes of a problem in a structured
  format
• Useful in organizing the ideas presented in a
  brainstorming session
• Organizes possible causes of a problem into
  groups material, machine, method, measurement,
  environment (mother nature), and man (operator)

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Cause and Effect Diagram

• Cautions
• Use the major categories to spark ideas for
  causes
• Use as few words as possible for the causes
• Make sure the group understands the "effect" or
  problem to be analyzed. Demonstrations and "show
  and tell" are helpful for group understanding.
• Remember to ask "why does this happen" instead of
  "who did this wrong."
• Cause/Effect must identify the ROOT causes before
  analysis is considered complete.

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Cause/Effect Diagrams
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Pareto Diagram

• Helps a team focus on causes that have the
  greatest impact
• Displays the relative importance of problems in a
  simple visual format
• Helps prevent shifting the problem where the
  solution removes some causes but worsens others

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Pareto Diagram

• Why use Pareto Charts?
• Used to display items in order of relative
  importance
• Used to identify the "vital few" problems on
  which to focus attention and resources
• Commonly known as the "80/20" rule. For example,
  where 80 of the defects are caused by 20 of the
  defect types

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Pareto Diagram

• Cautions
• Use different measurement scales to identify the
  most important problems. The most frequent
  problems are not always the most costly.
• Regrouping the data may be necessary to identify
  differences. The frequency of defects by defect
  type may show no difference while frequency of
  defects by machine may show a vast difference.
• Break down the broad causes into more and more
  specific parts to help identify the cause and not
  just the symptoms.
• Compare the process before and after alterations
  to the process to assess the impact of the
  changes.
• Only a beginning of the fact finding process
• Remember the most frequent problems are not
  always the most costly

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Scatter Diagram

• Supplies the data to confirm a hypothesis that
  two variables are related
• Provides both a visual and statistical means to
  test the strength of a relationship
• Provides a good follow-up to cause and effect
  diagrams

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Run Chart

• Monitors performance of one or more processes
  over time to detect trends, shifts, or cycles
• Allows a team to compare performance before and
  after implementation of a solution to measure its
  impact
• Focuses attention on truly vital changes in the
  process

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Run Chart

• Why use Run Charts?
• Used to show a trend in distribution
• Cautions
• Only a beginning in the fact finding process
• Collect data consistently and honestly

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Run Charts
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Deviation
Norm
Performance
Deviation
Time
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Frequency
Continuous
Cyclical
Random
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Trend
Stable

Deviation
Increasing

Deviation
Decreasing

Deviation
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Changes
Changed crew
Applied new cleaner
Switched suppliers
Hired new foreman
New Non-glare glass
6th anniversary
Measurement
3/1
3/27
4/10
4/15
Time
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Control Chart

• Focuses attention on detecting and monitoring
  process variation over time
• Distinguishes special from common causes of
  variation
• Serves as a tool for on-going control
• Provides a common language for discussion process
  performance

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Deviation
UCL
AVG
norm
LCL
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Poka-Yoke (Mistake-Proofing)

• An approach for mistake-proofing processes using
  automatic devices or methods to avoid simple
  human or machine error, such as forgetfulness,
  misunderstanding, errors in identification, lack
  of experience, absentmindedness, delays,
• or malfunctions

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Poka-Yoke Examples (from John Grouts Poka-Yoke
Page)
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Cause/Effect Diagram Exercise
Manpower
50 of all freshman at Lamar fail College Algebra
EFFECT
CAUSE