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1 Statistical Thinking for Management American Society for Quality Annual Quality Congress Anaheim, CA May 24-26, 1999

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Statistical Thinking for Management

American Society for QualityAnnual Quality Congress

Anaheim, CA

May 24-26, 1999

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Session T102

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Janice Shade

Nabisco

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ASQ Statistics Division

Team on Statistical Thinking:

Galen Britz - 3MDon Emerling - Ryobi Die CastingLynne Hare - NabiscoRoger Hoerl - General ElectricStu Janis - 3MJanice Shade - NabiscoRon Snee - Sigma Breakthrough Tech.

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Statistical Thinking Team Contributions

• The Role of ST in Management, AQC, Boston, ‘94– Quality Progress, Feb., ‘95

• ST for Business Improvement, AQC, Cincinnati, ‘95– Available through QIC

• Special Publication, Statistics Division, ‘96– Available through QIC

• How to Teach Others to Apply ST, FTC, ‘96– Quality Progress, June, ‘97

• How to Apply ST Effectively, FTC, ‘97• Improving Performance Through Statistical

Thinking, to appear

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Improving Performance Through Statistical Thinking

• Why ST is important?• What is ST?• How do you apply ST?• How to begin implementing ST

capability in an organization• Summary• Appendix - tools, case studies

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Statistical Thinking for Management

• Statistical Thinking Defined - Galen Britz• Statistical Thinking in the Organization - Ron Snee• How to use Statistical Thinking to Improve

Management Processes (Workshop) - Stu Janis• Group Summaries - All• Summary- Janice Shade

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Galen Britz

3M

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Definition

Statistical Thinking is a philosophy of learning and action based on the following fundamental principles:

• All work occurs in a system of interconnected processes,

• Variation exists in all processes, and• Understanding and reducing variation are keys

to success.

Glossary of Statistical Terms - Quality Press, 1996

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Definition

Statistical Thinking is a philosophy of

learning and action

based on the following fundamental principles:

Glossary of Statistical Terms - Quality Press, 1996

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Evaluation Based on Past Experiences or Perceptions

• We’ve always done it this way!

• We work with what we get!

• We do the best we can!

• I never thought about it!

• I’m so busy with the day to day troubles, I don’t have time to try that!

• That has no effect on the finished product (or service)!

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Evaluation Based on Data

THE KEY IS TO ASK WHY!!!

• Why is the material from the fabrication department machine so inconsistent?

• Why do so we constantly firefight?

• Why does our daily output vary so much?

• Why does every job result in a monumental task that takes forever to complete?

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Definition

Statistical Thinking is a philosophy of learning and action based on the following fundamental principles:

Glossary of Statistical Terms - Quality Press, 1996

•• All work occurs in a system of interconnected processes,

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FinishedGoods

or Services

Inputs Transformation Outputs

SuppliersInformation

Historical Data

Accounts PayableCar RepairBlending

Approvals

External Factors

- Materials - People

- Methods - Machines

- Environment - Measures

ProcessTransforms Inputs into Outputs

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Processes and Sub-Processes

CustomerCustomer Customer Customer

Sub-Process A

Sub-Process B

Sub-Process C

External Supplier

External Customer

Supplier Supplier Supplier Supplier

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Definition

Statistical Thinking is a philosophy of learning and action based on the following fundamental principles:

Glossary of Statistical Terms - Quality Press, 1996

•• All work occurs in a system of interconnected processes,

•• Variation exists in all processes, , andand

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Like it or not, variation is everywhere!

Know it, accept it, learn to deal with it!

• Our drive time to work each day.

• The quantity of production each shift.

• Departure time of our plane.

• ………

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DefinitionDefinition

Statistical Thinking is a philosophy of learning and action based on the following fundamental principles:

Glossary of Statistical Terms - Quality Press, 1996

•• All work occurs in a system of interconnected processes,

• Variation exists in all processes, and•• Understanding and reducing variation are keys

to success.

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Deming once said:“If I had to reduce my message for management to just a few words, I’d say it all had to do with reducing variation.”

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Variation and Targets

Variation can be thought of as:

1. Deviations around the overallaverage or

2. A deviation of the overall averagefrom a desired target.

Ave

TargetAve

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Reduced deviation around the Average and on Target

Voice ofProcess

Voice ofCustomer

Target

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Types of Variation

• Common Cause• Special Cause• Structural

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Pitfall

Valuing only quantitative data

Qualitative data are just as important.

Example: Idea data!!

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Improvementusing

Statistical Thinking

Process Variation Data Improvement

Statistical Thinking Statistical Methods

Philosophy Analysis Action

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Benefits of Statistical Thinking

Provides a theory and methodology for improvement:

• Helps identify where improvement is needed.

• Provides a general approach to take.

• Suggests tools to use.

A complete improvement approach includes all elements of Statistical Thinking:

Process - Variation - Data

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Ron Snee

Sigma Breakthrough Technologies, Inc.

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Use of Statistical ThinkingDepends on levels of activity and job responsibility.

Where we're headed

Managerial processesto guide us

Where the work gets done

Strategic

Managerial

Operational

Executives

Managers

Workers

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Process

SuppliersInputs

ProcessOutputs

Customers

S I P O C

A series of activities that converts inputs into outputs

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INTE

RFA

CES

IBM Core Processes

Market Place

Business Processes

PlanningFinancialPersonnelMgmt. Info. Sys.LegalCommunicationsPublic Relations

Product ProcessesEnterprise ProcessesTranslationRequirements

Collections and Definition

Market Segment

Design

Development

Manufacturing

DeliverySellingOrdering

DistributionBillingCollection

Service

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Examples of Operational Processes

• Manufacturing• Order Entry• Delivery• Distribution• Billing• Collection• Service

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Examples of Statistical Thinking at the Operational Level

• Work processes are flowcharted and documented

• Key measurements are identified.– Time plots displayed

• Process management and improvement utilize:– Knowledge of variation, and– Data

• Improvement activities focus on the process, not blaming employees.

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Examples of Strategic Processes

• Strategic Plan Development• Strategic Plan Deployment• Acquisitions• Corporate Budget Development• Communications - Internal and

External• Succession Planning and Deployment• Organizational Improvement

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Examples of Statistical Thinkingat the Strategic Level

• Executives use systems approach.• Core processes have been flow charted• Strategic direction defined and deployed.• Measurement systems in place.• Employee, customer, and benchmarking

studies are used to drive improvement.• Experimentation is encouraged.

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Examples of Managerial Processes

1. Employee Selection2. Training and

Development3. Performance

Management (including coaching)

4. Recognition and Reward

5. Budgeting

6. Setting Objectives and Goals

7. Project Management

8. Communications9. Management

Reporting10. Planning

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Examples of Managerial Processes

Objectives & Goals

Planning

Budgeting

ManagementReporting

Core Business Processes

Customers

EmployeeSelection

Training &Development

Recognition& RewardsPerformance

Management

Communication

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Examples of Statistical Thinking at the Managerial Level

.

• Managers use meeting management techniques• Standardized project management systems are

in place.• Both project process and results are reviewed.• Process variation is considered when setting

goals.• Measurement is viewed as a process.• The number of suppliers is reduced• A variety of communication media are used.

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Personnel Requisition Process

Resume Sentto HiringManager

ResumeReturnedby HiringManager

ApplicantInterviewedby Company

ApplicantInterviewed

by Consultant

New EmployeeStarts Work

ResumeReceived

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R&D Budgeting Process

R&D Senior VP ReviewBoard ofDirectorsReview

Budget #1Initiatives

Budget #2Personnel &Funding ($)

Budget #3Final

BudgetDeployment

Business Unit Budget Preparation

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Variables Affecting Managerial Processes

EmployeeBackground & Skills

Boss’s Needs

Other Managers’Needs & Actions

Market PlaceDemands

ManagingProcesses

Productand

ServiceProcesses Customer

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Example - Effect of Managerial Processes on Customers

Recruitingand

Hiring

Training

Recognitionand

Reward

Motivatedand

CapableEmployees

Good Products

andServices

HappyCustomer

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Robustness - An Underused Concept

• Key aspect of Statistical Thinking• Reduce the effects of uncontrollable variation

in:– Product design– Process design– Management practices

• Anticipate variation and reduce its effects

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Robustness of Product and Process Design

• A third way to reduce variation• Anticipate variation

– Design the process or product to be insensitive to variation

• A robust process or product is more likely to perform as expected

• 100% inspection cannot provide robustness

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Robust Products are Designed in Anticipation of Customer Use

• Washing machine tops• User-friendly computers and software• Low-maintenance automobiles• 5 mph bumpers• Medical instruments for home use

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Product and Process Robustness

• Product Performance is insensitive to variations in conditions of manufacture, distribution, use and disposal.

• Process Performance is insensitive to uncontrollable variations in process– Inputs– Transformations - activities - steps– External factors

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Robustness in Management

• Develop strategies that are insensitive to economic trends and cycles

• Design a project system that is insensitive to – Personnel changes– Changes in project scope– Variations in business conditions

• Respond to differing employee needs– Adopt flexible work hours– Provide “cafeteria” benefits package

More ...

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Robustness in Management(Continued)

• Enable personnel to adapt to changing business needs

• Ensure meeting effectiveness is not dependent on facilities, equipment, or participants

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Understanding Human Behavior

• Different people have different methods and styles of working, learning and thinking

• Different people take in, process and communicate information in different ways

• People vary --- they are different:- Day to day- Person to person- Group to group- Organization to organization

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Three Ways to Reduce Variation and Improve Quality

Control the Process:Eliminate SpecialCause Variation

Improve the System:Reduce Common Cause Variation

Anticipate Variation:Design RobustProcesses and Products

Quality Improvement

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Process Robustness Analysis

• Identify Those Uncontrollable Factors that Affect Process Performance– Weather– Customer Use of Products– Employee Knowledge, Skills, Experience,

Work Habit– Age of Equipment

• Design the Process to be Insensitive to the Uncontrollable Variations in the Factors

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Stu Janis

3M

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Workshop Activities

• Objective– Apply concepts to a managerial process in your

organization

• Concept– Groups will discuss how statistical thinking can be

applied to a managerial process.– Results will be presented at the end.

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Workshop Process• Form into groups of about 10.• Your group will be assigned a managerial

process.• Answer the question: How can Statistical

Thinking be applied to improve the ________ process in my organization?

• Record results on transparency.• Appoint a representative (the person with the

next birthday?) to present the results.

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Things to Think About… (and Present)

• What is the PROCESS?– Suppliers --> Inputs --> Process --> Outputs -->

Customers

• What could cause VARIATION in the process and its outputs?

• What DATA would you use to monitor and improve the process?

• How could the process be made more ROBUST?

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Examples of Managerial Processes

1. Employee Selection2. Training and

Development3. Performance

Management (including coaching)

4. Recognition and Reward

5. Budgeting

6. Setting Objectives and Goals

7. Project Management

8. Communications9. Management

Reporting10. Planning

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Janice Shade

Nabisco

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Using Statistical Thinking To Improve Processes

ProcessesServe

Customers

ProcessPerformance

Varies

MeasureProcess

Performance

Use Statistical Tools to:- Analyze Process Data- Understand Process Variation- Improve Processes- Better Serve Customers

Goal is to:Delight

Customers

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Check Act

Do Plan

Check� Assess major problems and

root causes� Define the scope of the

project,� Identify the people who will

be affected by the project

Do� Implement the

plan.� Assure continued

process performance.

Act� Fix the obvious.� Decide how to

approach the issue or problem.

Plan� Set project goals

and expectations.� Develop the

project plan.

CAPDo DiagnosticTips for Statistical Thinking

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Tips for Statistical Thinking

• Flow Diagram• Pareto Charts• Cause & Effect • Histograms• Run Charts• Control Charts• Scatter Diagram

• Affinity Diagram• InterRelationship

Diagram• Tree Diagram• Matrix Charts• Arrow Diagram• Process Decision

Quality Tools Management Tools

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Tips for Statistical Thinking

Start with the customer.Identify customer requirements and expectations.

Start small.Pick a process that is not very detailed and does not involve many functions or work groups. Small “wins” build confidence and teamwork.

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Tips for Statistical Thinking

If a process or system is stable -- showing only common causes of variation.

Use the tools of improvement to study all the data (not just the “good” or the “bad” points) and identify factors that cause variation. Determine what needs to be permanently changed to achieve a different level of quality.

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Tips for Statistical Thinking

If a process or system is not stable -- showing signs of special cause …

– Use the tools of problem-solving to identify the root cause. Try to identify exactly when, where, how, and why the process changed.

– If a Special Cause hurts the process, develop procedures to eliminate the return of the problem. If a Special Cause is beneficial, develop procedures to make it a permanent part of the process.

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Watch for: “Improving Performance Through

Statistical Thinking”