Some of the frequently asked questions related to the Six Sigma Methodologies are as follows :

(1)    What is the Six Sigma methodology?

Six Sigma is a statistically driven methodology which focuses on the elimination of the defects and implementation of a measurement-based strategy that leads to process improvement and variation reduction.  It is data driven and disciplined initiative for improvement in any project  from manufacturing to transactional and from product to service.

(2)    What is statistical representation of Six Sigma

The statistical representation of Six Sigma describes that a process must not produce more than 3.4 defects per million opportunities.  A Six Sigma defect is defined as anything that does not meet the customer satisfaction and a Six Sigma opportunity is the no of chances for the occurrences of a defect.  Process sigma is calculated by using a Six Sigma calculator.

(3)    What are the costs and savings of Six Sigma?

In order to significantly reduce costs and increase sales by applying the Six Sigma requires investing in training, organizational infrastructure and culture evolution. It will require money to make money.  Only leadership of the company can decide whether the investment in Six Sigma organization culture and employees worth the money.

Six Sigma can lead to significant savings to a company if it is implemented correctly.  The savings as a percentage of revenue vary from 1.2% to 4.5% and it is observed that Six Sigma is get rich slow methodology.  In Six Sigma implementation, the financial benefits of potential process improvement projects are quantified and applied to select and prioritize process improvement projects.

(4)     What is curriculum included in Six Sigma training whether conducted in-house or by a third-party consultant.

Six Sigma training is a key process for the implementation of Six Sigma. The Curriculum of any Six Sigma training depends on the professional certification level eg. Black Belt, Champion, Master Black Belt, Green Belt. Usually it covers the following aspects

Overview : Overview of Six Sigma, DMAIC Methodology Overview,DMAIC Versus DMADV (Design for Six Sigma) Overview, Financial Benefits of Six Sigma, The Impact of Six Sigma to The Organization, The Six Sigma Language, Project Prioritization, Launching a Six Sigma Initiative, Roles of the Six Sigma Organization, etc.

Define :  Overview of Define, Project Definition, Project Charter, (CTQs), SIPOC Diagram, Questions to Ensure a Successful Define Phase

Measure : Overview of Measure, Process Mapping (As-Is Process), Data Attributes (Continuous Versus Discrete), Measurement System Analysis, Gage Repeatability and Reproducibility, Measuring Process Capability, Calculating Process Sigma Level, Visually Displaying Baseline Performance, Questions to Ensure a Successful Measure Phase.

Analyze :  Overview of Analyze, Visually Displaying Data, Value-Added Analysis, Cause and Effect Analysis, Verification of Root Causes, Determining Opportunity for Improvement, Project Charter Review and Revision, Questions to Ensure a Successful Analyze Phase

Improve : Overview of Improve, Brainstorming, Quality Function Deployment, Failure Modes and Effects Analysis, Piloting Your Solution, Implementation Planning, Culture Modification Planning, Questions to Ensure a Successful Improve Phase

Control : Overview of Control, Statistical Process Control Overview, Developing a Process Control Plan, Documenting the Process, Questions to Ensure a Successful Control Phase

(5)     What is a Six Sigma champion?

A Champion is a Six Sigma professional who facilitate the leadership, implementation and deployment of Six Sigma philosophy in the organization. Their roles include creating the vision realizing the gains, defining the path for effective implementation of Six Sigma initiatives.

(6)     What are the best books for Six Sigma?

Some of the best books available on Six Sigma are as follows

• The Six Sigma Way: How GE, Motorola, and Other Top Companies are Honing Their Performance by Peter S. Pande et al, Robert P. Neuman, and Roland R. Cavanagh
• The Six Sigma Handbook: The Complete Guide for Greenbelts, Blackbelts, and Managers at All Levels, Revised and Expanded Edition by Thomas Pyzdek
• Six Sigma for Dummies by Craig Gygi, Neil DeCarlo, Bruce Williams, and Stephen R. Covey
• The Lean Six Sigma Pocket Toolbook: A Quick Reference Guide to 100 Tools for Improving Quality and Speed by Michael L. George, John Maxey, David T. Rowlands, and Michael George
• Statistics for Six Sigma Made Easy by Warren Brussee
• Lean Six Sigma for Service : How to Use Lean Speed and Six Sigma Quality to Improve Services and Transactions by Michael L. George
• What Is Six Sigma? by Pete Pande and Larry Holpp
• What is Lean Six Sigma by Michael L. George, David Rowlands, and Bill Kastle
• The Complete Idiot’s Guide to Lean Six Sigma by Breakthrough Management Group and Neil DeCarlo .

(7)     What is the difference between the Six Sigma DMAIC and DMADV methodologies?

DMAIC is used for the purpose of incremental improvements to the existing  processes, while DMADV is used for innovative improvements in new processes and designs. It is also called as DFSS.

They have similar first three steps(Define, Measure and Analyze) while they differ in last two steps in DMAIC it is improve and control while in DMADV it is design and verify.

(8)     What is the definition of DPMO or DPPM?

Defects per Million Opportunities: It is a measure of the error rate per million opportunities and quality improvement methods aims to minimize it.

(9)      How much salary does a Six Sigma Belt make per year?

The salary survey provides a first look at the worldwide average salary and bonus for each of the four roles:

Salary          Bonus

Black Belt                            $ 76,241        $9,698

Master Black Belt              $104,008       $19,933

Champion                           $93,625         $22,618

Deployment Leader          $108,361       $20,935

(10) How do I begin the Six Sigma implementation process?

One can begin implementing the Six Sigma by following the basic steps:

• Selecting the right project and commitment to the project.
• Define the project scope and goals based on customer specifications.
• Measure the defects in the current system and performance by using the statistical data analysis
• Analyze the system by identifying the defects and their causes.
• Improve the system by finding ways to do things faster and better.
• Control the new process by modifying systems and measuring processes, using the customer feedback and statistical tools.

(11) How do I calculate my process sigma level?

Five step process to calculate your process sigma is as follows :

• Define the Opportunities
• Define the Defects
• Measuring  the  Opportunities and Defects
• Calculate the Yield
• Look Up Process Sigma on Sigma Conversion Table

(12) How are Six Sigma projects reviewed?

Six Sigma projects are reviewed by performing status checks which involves reviewing the timelines, validation of proper Six Sigma tool used monitoring of the key progress deliverables.

(13) Why Hire a Six Sigma Consultant ?

Six Sigma consultants are much better than the employees of the organization. They are more skilled at explanations. They are unbiased in their recommendations and they have rich experience in implementing Six Sigma in various projects.

(14) What are the best institutes for online six sigma training?

Some of the schools which offer six sigma courses online via distance learning are as follows

(1)   Kaplan University

(2)   Capella University

(3)   Grand Canyon University

(4)   Villanova University

(5)   Morestream University

(6)   Regis University

(7)   eCornell University

(8)   Baker College Online

Apart from that a lot of information is also available on following sites.

http://www.motorola.com/content.jsp?glob…
http://www.isixsigma.com/sixsigma/six_si…

Regression analysis is the statistical tool that assists in assessing the relationship between two variables. The association between the two variables is quantified for example by placing X & Y in a line or on a plane in such a way that all the points are evenly distributed on a plane or lies in a line.

This tool is used to depict the relationship between a variable with one or more other variables. Different types of Regression analysis that can be used are as follows:

Simple Regression: It is the simplest form of Regression Analysis which has only two variables namely X & Y that comply with each other. It is applicable with both Linear & Nonlinear Regression analyses that has one variable.

Polynomial Regression: It is a nonlinear equation that includes any number of data or terms in an equation. They are not strictly nonlinear equations, however it can be a linear equation when one variable is Constant & compared with other variable. It is applied for interpolation & graphing purposes.

Calibration Model: It includes two variables where large numbers of known values are measured and as per the values an equation is drawn. It is later used to know the unknown values by inversing the predicted value.

Multiple Regressions: This model defines one variable as a function to multiple numbers of variables and used to include data to a linear equation with two or more variables.

Nonlinear Regression: It is a type of analysis which involves a nonlinear combination of the variables that depends on one or more independent variables.

Partial Least Squares: It is designed to develop statistical models where multiple independent variables are related to multiple dependent variables. It is useful for the prediction of many values. It is largely used by Chemical Engineers & Chemometricians.

Six Sigma methodologies follow the principles of improvement in quality which is not entirely new however it is focusing on key areas while implementing its methods. This focus on key areas including elimination of wastes and risk management has made it highly successful across the industries.

Management of risk and avoiding the fad cycle creates a big difference between Six Sigma and other quality management methods.  It demands consistent high level of commitment and in depth understanding for ensuring real improvements.

The success of Six Sigma lies in the fact that it actively manages ‘soft’ social factors, in spite of being a ‘hard’ scientifically-based methodology.

One of the main reasons of the success of Six Sigma is that it leads to the improvement of entire business procedure covering the implementation in each and every process of organization. Six Sigma is not only an improvement toolkit but also engages managers in activities such as championing projects and programs.  This results in commitment from the professional as they are involved.

Six Sigma requires senior managers to personally invest time and attention and ensure they get return on their investment on Six Sigma training and implementation.  Six Sigma requires its managers to constantly deliver significant improvements and their performance is measured by the improvements they made to the process. Black Belts are given power to bring about the changes in the organizations.

The standard approach to Six Sigma is to ‘give it teeth’, for example in the way GE requires its businesses to constantly make and report significant improvements. When managers are measured on the changes they make, then in the words of the old saw ‘what gets measured gets done’.  Black Belts are also often given positions of authority, adding to their expert power in being able to convince people to engage in improvement activities.

Implementation of Six Sigma includes in-depth training that leads to real expertise and thus a well-educated Black Belt can approach a problem with a wealth of expertise and experience. Statistics is the mathematics of reality that highlight real significance and it has a social dynamic in that it adds credibility to Six Sigma Professionals.

Six Sigma recognizes that full-time improvement professionals are a critical part of the successful implementation where the professionals are engaged and committed to bring improvement that is both important and difficult enough.

Recession has taken its beating on the major economies of the world and companies are looking for the way out and struggling to survive by taking various bold move steps involving cost cutting measures. In this market scenario there is impending need for evaluating Six-Sigma principles.

Six Sigma Methodology is now being widely used for improving efficiencies in corporate business world and it has resulted in rich dividends by practicing of Six Sigma disciplined approach. However the penetration of Six Sigma outside the corporate world is very limited and this raises the relevant question regarding the role of Six Sigma in resolving the social and national issues.

Six sigma professionals have been looking for the change in existing business procedures but their scope is limited to their own companies. Black belts professionals  are the required for bringing the desired change and they are doing it by organizing small meetings, discussing the issues at hand, finding the solutions, and implementing them.  The experience and skills of trained Black Belt can lead to changes which are difficult to achieve.

Risk Management has been the keyword for the survival of organizations in these turbulent times. It can avoid the companies from financial breakdown. Audit firms had failed in understanding the quantum of risk and there were no control and contingency plan in place to avoid this kind of failure.

By looking at the current world scenario one can make out that majority of world population is living below the poverty line and their productivity is restricted to earning their livelihood. Lack of skilled workforce, duplication of work, lack of opportunities etc contributes towards non productivity in most parts of the world. By implementing Six Sigma desired changes can takes place.

There are many areas where application of Six Sigma skills can lead to elimination of waste in the system. Today there is urgent need of applying Six Sigma Methodologies to beat the recession and it has to implemented effectively with complete cooperation from every strata of society and cooperation among various nations.

Six Sigma – First Generation (SSG 1)

The first generation of Six Sigma refers to the era between 1986 and 1990. It is also called as SSG 1 for short.  This was a concept which was devised and pioneered at Motorola. Motorola focused on the Statistical approach for improvement in business processes and practiced the Six Sigma Metrics as in Measured Defects Per Million Opportunities (DPMO)

During this generation the organizations focused on various strategies to achieve the quality improvement initiative by elimination of defects in the system, improving the product and service quality, reducing the cost associated with the products and processes and ensuring the continuous process improvement.

Six Sigma – Second Generation (SSG 2)

In the 1990s, there was a shift in the focus of Six Sigma Methodologies from the manufacturing sectors to service sectors. It was a phenomenal phase where professionals aimed to achieve improvement by directing their efforts from product quality to business quality.

General Electric Corp.  marked the beginning of second generation of Six Sigma. It is also known as SSG 2.  In second generation, Six Sigma became a business centric system leading to improvement in management.  Six Sigma principles were applied across the organization in various related processes. Emphasis was given on bringing dollars to the bottom-line by using the strong measurement techniques and candidates having high potential were selected as Black Belts.

Six Sigma – Third Generation (Gen III)

Third Generation of the Six Sigma was developed after the year 2000  and it is also known as Gen III. This generation focuses on the principles and methods of delivering the products and services which have real value in the eyes of the customers .

This generation opines the combination of Lean Manufacturing Techniques and Six Sigma which is termed as Lean Six Sigma. Integrating Six Sigma with other quality improvement programs resulted in path breaking improvement across various sectors. Gen III program was started by Korean steel maker Posco and electronics maker Samsung.

Six Sigma has established itself as an effective quality improvement technique after it was successfully implemented in various organizations all over the world. Many large organizations have improved the quality of manufactured goods or services delivered.

However, the full potential of Six Sigma has not been realized so far and the extent of profitability of Six Sigma in various different sectors is yet to be explored. This is because numerous competent small to medium level enterprises are yet to implemented Six Sigma programs.

Usually these enterprises have all the resources for the implementation of Six Sigma initiatives, but they are wary of the final certification, as they believe that Six Sigma is beneficial only for large organizations.  The future is bright for Six Sigma programs with the increasing awareness in small and medium enterprises regarding the potential benefits of implementing the Six Sigma initiatives.

Six Sigma is different from other quality management tools such as TQM or Kaizen Events although it may appear similar. Implementation of other quality management programs often leads to a stage after which no further quality improvements can be achieved while focus of Six Sigma is on taking quality improvement processes to the next level.

Six Sigma can be applied to every business process of an organization. This clearly suggests that scope of Six Sigma is much broader than other quality management programs and it may outlast them in the future.

Six Sigma is likely to remain as one of the key initiatives for improvement of management process.  Six Sigma professionals are trying to integrate Six Sigma with other existing innovative management practices to make Six Sigma method even more attractive.

Integrating Six Sigma with Total Quality Management, Human Resource Functions, Lean Production, ISO 9000, ISO 9001, and the capability maturity model is one of the key areas of interest for researchers and practitioners to maximize the positive effect of the Six Sigma method.

Six Sigma has resulted in the path breaking improvement in various companies across the globe where it is implemented correctly; however Six Sigma has its share of criticisms as well.

One of the more common criticisms is that Six Sigma does not offer anything new and different strategy and it is popularized simply as a marketing tool. Six Sigma was inspired from the earlier work in the areas of quality improvement and adopted the best features of previous quality versions, however it offers unique feature of its own as in measures such as defects per million opportunities.  It’s proven that defect and defectives counts offer tangible, measurable results.

Another criticism is that Six Sigma is more of a corrective action system rather than taking a preventive and proactive approach to problems. However, Six Sigma does include the education and training of the entire workforce as well as creation of an infrastructure of experts who focus on projects to improve quality, timeliness and cost.

Another criticism suggests that Six Sigma is merely about appraisal system and that appraisal programs aren’t useful. In realty, appraisals are great tools for identifying and tracking improvements, which is critical to any project.

Some critics have argued that the success of quality programs depends more on the right organizational culture than on any corrective or preventive program. It means that improvement results from the internalization of quality program. Six Sigma is not merely a corrective program and it recognizes that cultural issues including leadership development as the most important issues to be addressed to bring about the improvement of any organization.

Critics have suggested that Six Sigma did not bring quality improvement in all the organizations where it was implemented. However, in majority of these cases it is not the tools which have failed but the mangers and other professionals failed to implement them correctly.

One of the technical criticisms suggested that assumption of a process mean to be 1.5 sigma off target is incorrect. Keeping the process mean exactly on target is another ridiculous argument. As defined in process capability studies, Sigma is the short-term within sample variability. Therefore the 1.5-sigma shift allows for variation of the mean related to the target.

Another technical criticism is that the normal distribution is simply a model and most of the processes are not represented by it.  Although it is fact that normal distribution is a model but it is very useful and reasonable for many situations. Furthermore, any realistic process model will predict a much larger probability of producing a product outside the specifications.

Six Sigma gives emphasis on the rigidity of the process which basically contradicts the innovation and kills the creativity. The innovative approach implies deviations in production, the redundancy, the unusual solutions, insufficient study which are opposite to Six Sigma principles.

Six Sigma is a bit gimmicky and simply a rebranding of the continuous improvement techniques and tools as practiced by Toyota. It thus promotes outsourcing of improvement projects with lack of accountability.  Six Sigma implementation constantly require skilled man force. Thus control and employee dedication are hard to accomplish if it’s not implemented regularly.

To summarize, Six Sigma is a proven strategy for improvement in process quality that addresses leadership, tools and infrastructure issues. Many important issues were neglected by previous programs.  Many companies, who have achieved success, praise the accomplishments of the Six Sigma initiatives.

Six Sigma has met with success in almost every sector of the business where it is applied. Quality professionals and industrial statisticians advocate the beneficial roles of Six Sigma in improving the culture of the organization. Six Sigma principles and methodologies have been incorporated in the curriculum of various engineering programs.  Constructive criticism of Six Sigma should be informed and based on logic and it can be useful.