The term “Six Sigma” may seem difficult to comprehend at times, but is actually very easy to explain. The term is derived from a character in the Greek alphabet, which is used for representing a standard variation in statistical mathematics. Statistically, Six Sigma can be defined as a near perfect method of production that restricts the number of defects to less than 3.4 for every million opportunities that exist for a defect to occur. This makes Six Sigma one of the preferred quality management techniques for achieving near perfect business processes through process improvement.
Data Driven And Disciplined Approach
Six Sigma follows a disciplined and data driven approach for eliminating defects in any type of business process, whether it is the product manufacturing process or after sale customer service. The two most commonly used methodologies in quality improvement projects are the DMAIC process (define, measure, analyze, improve, control) and the DMADV process (define, measure, analyze, design, verify). The former is used for improving the quality of business processes that have not met customer specifications and require improvement. The latter is used for developing new products or business processes that conform to 6-Sigma quality levels. Both the processes are carried out under the guidance of Green Belts and Black Belts, who in turn are guided by Six Sigma Master Black Belts.
Companies often want to know exactly how many benefits can be derived from Six Sigma training. Just to get an idea, one can look at the financial data of General Electric, one of the companies that have successfully implemented Six Sigma training. It is estimated that the total value of benefits derived from the training was close to a staggering $ 10 billion in the five years after implementation. It is estimated that on an average, Six Sigma Black Belts help companies save $ 230,000 per project. Given that most companies can execute 4 to 6 such projects per year, the total savings can translate into $ 920,000 to $ 1,380,000 per year.
Selection Process
After selecting the most appropriate type of training, a company needs to find the right consultant who has the necessary skills and experience in implementing Six Sigma programs. The selection of the training consultant will depend on the type of Six Sigma program that the company is planning to implement. Some programs are implemented all throughout an organization whereas others are implemented in a specific area only such as individual functional departments. The decision regarding the selection of the consultant needs to be made only after consulting other employees, as they are the ones who will eventually interact with the consultant during the implementation process.
After getting approval from the employees, it is advisable to seek references from business associates in other companies that have implemented such projects and can provide the necessary insights. Companies need to interview potential trainers and ask questions regarding their previous work relationships, referrals, total number of candidates trained by them till date, training materials used, earlier projects they have worked on, and their qualifications. This is essential since companies need trainers with a great deal of real-world experience. Companies need to inquire in depth about the type of training that the trainer is willing to provide. Usually, companies prefer training firms that operate online help desks for helping clients in dealing with problems that might arise after the training has been completed.

Six Sigma methodologies use statistical tools used to transform raw data into information. Based on the results, further actions are taken. Statistical tools and related aspects of Six Sigma methodology comprises about half of Six Sigma. In addition, Six Sigma places a lot of emphasis on graphical interpretation of data collected during the course of measurements.
The importance of statistical methods emanate from the fact that many hypotheses can be disproved with sufficient statistical data. The significance of statistical methods in Six Sigma increases with any increase in sample sizes. The statistical methods quantitatively facilitate evaluation of the performance of any process. The purpose of this being to tackle the cost of poor quality (COPQ) first, Six Sigma has a broader scope than the traditional cost effectiveness model.
Some Important Statistical Methods In Six Sigma
Variations in processes are measured in terms of deviation from the mean and data falling within the acceptable statistical limits. Graphical representation of this data helps companies to visualize things with greater accuracy. Let us examine a few of the most commonly used Six Sigma statistical methods.
Control Chart
The deviations within the acceptable limits (upper & lower) are due to common causes. Anything falling beyond the limits is attributable to some specific cause. For example, take the case of writing your name ten times. Although there are similarities, you probably won’t be able to find any two signatures being exactly the same. The reason is an inherent variation that produces reasonable results within limits and is termed as ‘common cause’. Special causes are those due to forced errors. A control chart has a mathematical mean line in the center and two limit lines. The third component of the Six Sigma control chart is the performance data, which is plotted over time.
You can seek special causes and track common ones through control charts by looking for:
• One set of data falling beyond the acceptable limits (special cause)
• Greater than 6 data sets climbing or declining steadily within limits
• Eight or more subsequent data sets falling on one side of the mean
• Data falling alternately across the mean line
Interpretation emphasizes seeking out the special cause that brings stability to process variation. The real fun here lies in removing the common cause and induced variations also.
Brainstorming & Affinity Group Tool
Brainstorming generates and polishes creative ideas based on the principle that two heads are better than one. An affinity diagram is used to organize & develop brainstorming by fine tuning initial and raw thoughts and removing uncertainties. The advantage of this is that it obviously stimulates for generation of more ideas. The affinity diagram was not originally intended to be a quality management tool. First devised by Kawakita Jiro, the affinity tool emphasizes the need for sorting and titling the data only at the end. A typical affinity diagram organizes the brainstormed ideas on its left panel. On the right side are ideas neatly grouped into affinity sets. Reasons for an idea belonging to a particular set are not given particular importance, but all ideas are clarified. An idea may be present in a single group if it has any resemblance to another.
If there is one thing that summarizes the importance of statistical methods in Six Sigma, it can be none better than a saying, famous in Six Sigma circles – “In God we trust, all the rest bring data”. Need we say more?

Although the program has proven wildly successful in many different cases, other companies have tried to implement the Six Sigma system with results that can best be described as mixed. A large part of the “mixed” (and you can read that as “negative”!) results can be attributed to an improper implementation of the Six Sigma process.

Six Sigma is a methodological strategy by which errors in a company’s current processes and plans are identified and strategies to rectify the same are formulated. It is fact-based technique, involving a lot of data handling, which provides scientific results for cost cutting and reduction in waste of resources. Today, many organizations, large and small scale, are applying Six Sigma to ensure improved, faster and cheaper services to their consumers without compromising on the quality quotient.
Various Levels
Implementation of Six Sigma requires professionals who have been trained in the program and have had exposure to practically applying the concepts in different organizations across industries to know how to go about its application on the job. There is a Six Sigma certification program that has to be undertaken for gaining knowledge about this particular quality measurement practice. Six Sigma certification is similar to other professional courses in that after having cleared specified guidelines and followed the required procedure, individuals are certified as capable of employing the gained knowledge in their respective field. There are several stages of the program and with each qualifying level, certain tests that have to be cleared. These levels are labeled in the same manner as a martial arts certification grade. There are various belts such as green belt, black belt and master black belt awarded to professionals who complete corresponding stages of the course.
Green Belt
The first level is completed when an individual finishes two weeks of training and passes the qualifying exam. This level is termed Green Belt, which teaches all the essential methodologies. The curriculum for the Green Belt involves DMAIC, which stands for five interrelated phases: Define, Measure, Analyze, Improve, and Control. It defines customers, their needs, recommended products and services, the assignment limits and plotting process flow to improve current methods. It measures performance by developing and collecting data from numerous sources and scrutinizing it for flaws by comparing it with surveys. The Analyzing phase bridges the rift between present methods and targeted results. Improving stage works out various solutions to redefine the earlier processes and deploys implementation plans. The Control stage teaches how to maintain the new changes that have been introduced and maintain the documentation and contemporary systems in accordance with the goals.
Black Belt
The Black Belt is awarded to a professional who completes four weeks of training, which involves Green Belt curriculum as well. This phase’s curriculum covers Green Belt subject matter as well. Black belt certified personnel usually train other Six Sigma aspirants and Green Belt holders, and in the process improve their abilities and skills as well. The Black Belt level enables individuals to master the Six Sigma roadmaps, extensive arithmetical methodologies and cross-functional process improvement. Black belts usually take up responsibility as Six Sigma team leads.
Master Black Belt
A person who has undertaken more than the required four weeks training and implements it in an organization as a Six Sigma program manager is awarded the Master Black Belt. These personnel are responsible for imparting knowledge to help Green Belt level and Black Belt level learners in improvising on their projects. They apply their skills in an organization by coaching other employees and helping them achieve the Green Belt and Black Belt certification without the company having to spend on training separately.

Six Sigma methodologies use statistical tools used to transform raw data into information. Based on the results, further actions are taken. Statistical tools and related aspects of Six Sigma methodology comprises about half of Six Sigma. In addition, Six Sigma places a lot of emphasis on graphical interpretation of data collected during the course of measurements.
The importance of statistical methods emanate from the fact that many hypotheses can be disproved with sufficient statistical data. The significance of statistical methods in Six Sigma increases with any increase in sample sizes. The statistical methods quantitatively facilitate evaluation of the performance of any process. The purpose of this being to tackle the cost of poor quality (COPQ) first, Six Sigma has a broader scope than the traditional cost effectiveness model.
Some Important Statistical Methods In Six Sigma
Variations in processes are measured in terms of deviation from the mean and data falling within the acceptable statistical limits. Graphical representation of this data helps companies to visualize things with greater accuracy. Let us examine a few of the most commonly used Six Sigma statistical methods.
Control Chart
The deviations within the acceptable limits (upper & lower) are due to common causes. Anything falling beyond the limits is attributable to some specific cause. For example, take the case of writing your name ten times. Although there are similarities, you probably won’t be able to find any two signatures being exactly the same. The reason is an inherent variation that produces reasonable results within limits and is termed as ‘common cause’. Special causes are those due to forced errors. A control chart has a mathematical mean line in the center and two limit lines. The third component of the Six Sigma control chart is the performance data, which is plotted over time.
You can seek special causes and track common ones through control charts by looking for:
• One set of data falling beyond the acceptable limits (special cause)
• Greater than 6 data sets climbing or declining steadily within limits
• Eight or more subsequent data sets falling on one side of the mean
• Data falling alternately across the mean line
Interpretation emphasizes seeking out the special cause that brings stability to process variation. The real fun here lies in removing the common cause and induced variations also.
Brainstorming & Affinity Group Tool
Brainstorming generates and polishes creative ideas based on the principle that two heads are better than one. An affinity diagram is used to organize & develop brainstorming by fine tuning initial and raw thoughts and removing uncertainties. The advantage of this is that it obviously stimulates for generation of more ideas. The affinity diagram was not originally intended to be a quality management tool. First devised by Kawakita Jiro, the affinity tool emphasizes the need for sorting and titling the data only at the end. A typical affinity diagram organizes the brainstormed ideas on its left panel. On the right side are ideas neatly grouped into affinity sets. Reasons for an idea belonging to a particular set are not given particular importance, but all ideas are clarified. An idea may be present in a single group if it has any resemblance to another.
If there is one thing that summarizes the importance of statistical methods in Six Sigma, it can be none better than a saying, famous in Six Sigma circles – “In God we trust, all the rest bring data”. Need we say more?

Six Sigma is usually associated with the complete overhaul of existing business processes, to reduce shortcomings and improve the quality of goods and services. Due to this belief, many companies with insufficient resources often avoid implementing the 6 Sigma concepts and methodologies in their business processes. These companies are often unaware that the Six Sigma concepts and methodologies can also be implemented with innovative shortcuts. These shortcuts are known to have the same affect on the quality as the standard 6 Sigma implementation processes.

The new emphasis on quality is why businesses have now become more concerned about maintaining the quality of products and services than ever before. This in turn has created a huge demand for quality-assurance professionals who have the necessary domain knowledge and expertise to ensure the desired level of quality.

Lean manufacturing combined with Six Sigma have been combined to form Lean Six Sigma. Both are basically techniques to improve business. The concept of Lean manufacturing comes from Toyota Production System while Six Sigma owes its origins to Motorola. Both concepts when combined, can transform organizations. Elimination of waste and reduction in the time cycles are the goals of Lean while Six Sigma focuses on improving quality and reducing variability. The goal of any business is to maximize shareholder value. This can be achieved by reduction in cost, increase in quality, increase in process speed, a better return on invested capital and improved customer satisfaction.When Lean Six Sigma is applied to businesses, there are significant benefits in terms of improved lead time, reduction in costs and enhancement of quality. The US Army has adapted the Lean Six Sigma to its growing needs to eliminate waste in time, money and material. To this end, the US Army Installation Management Command or IMCOM for short has drawn up a training program for enhancing productivity and reducing costs. IMCOM has a training program for bringing about transformation in the US Army through Lean Six Sigma. The curriculum includes awareness and conceptual training on how the concept of Lean Six Sigma fits into the overall strategy of the US Army to make it efficient and productive. Hands-on understanding of the process is given; participants are imparted knowledge on how to identify projects and select them for the purpose of applying Lean Six Sigma. The roles and responsibilities of a Leader are highlighted. The curriculum also includes training in tools and skills necessary for effective and efficient implementation of Lean Six Sigma. Personnel have divided into Green Belts and Black Belts. Green Belts are taught to be effective team members. They are taught the DMAIC concept of six Sigma. DMAIC is the acronym for, Measure, Analyze, Improve and Control.Black Belts are those who will use the processes and tools required to implement DMAIC methodology. Black Belts are taught through simulation, case studies, exercises and examples. The application of Lean Six Sigma in the US Army has resulted in reduction of expenditure and improvement in productivity through contracting, manufacturing, administrative services and recruiting. The Red river Army Depot at Texas in one such example. The US Army was able to save $30 million on the production of Humvees. The unit upped its production from 3 Humvees a week in 2004 to a whopping 32 mission ready Humvees in a day by 2006. The Regional Readiness Command at Utah has been able to reduce   the cycle time from 90 to 21 days in awards processing. Previously, the deployment preparation time for a battle-rostered unit was 30 days. On account of Lead Six Sigma this time period has been brought down to just 3 days! LEADS, the system through which army starts the recruitment   process of prospectives, has improved on account of Lead Six Sigma. The steps have been reduced from 32 to 11. This has brought down the time taken for the recruitment by 40%. The repair cycle time at the Pine Bluff Arsenal at Arkansan reduced by 90%. The production of M-40 protective masks increased by 40%, on account of Lean Six Sigma. There was an $11.9 million reduction of cost in Patriot air defense missile system recapitalization. At the Corpus Christi Army Depot in Texas, the time taken to rebuild the UH-60 Blackhawk decreased from 256 days to around 70. In the backdrop of fiscal constraints that the US Army is facing, these cost savings have come in as a morale booster. While, undoubtedly there have been a number of examples of costs savings and improvement in productivity on account of implementation of Lean Six Sigma, more profound has been the impact of the common US soldier. Despite the initial resistance, wherever it has been implemented in the US army, it has met with success. Peter Peterka is the President of SixSigma.us. For information on Six Sigma, Six Sigma Certification or Online Six Sigma programs contact Peter Peterka.