What is Six Sigma?

Six Sigma is a quality management methodology used to reduce defects and maintain consistency in products.

Six Sigma is mentioned in the PMBOK Guide and included in the PMP Exam Content Outline, so you will see questions on this topic on your exam.

I see that many PMP exam reference books do not discuss this methodology. This is an important concept and you should know it.

Six Sigma

Motorola developed Six Sigma in 1986 to remove the causes of possible defects from a process before it started.

This methodology was successful; GE adopted it and had excellent results. The fame of the Six Sigma methodology skyrocketed, and many manufacturing industries adopted it.

Six Sigma is a data-driven process, customer-focused, results-oriented, product improvement methodology. The goal is to improve quality to the extent where only 3.4 failures per million are allowed, or products have 99.9967% accuracy.

The chart below shows the Six Sigma graph.

Image Credit: Jayen466, Fleshgrinder [Public domain], via Wikimedia Commons

从这张图,你可以说,六西格玛是six standard deviations on either side of the mean. LSL stands for Lower Specification Limit, and USL stands for Upper Specification Limit. Any measurement outside of these limits is considered a defect. The mean line is the target, and this is the ideal measurement.

六西格玛组织的角色

You can divide the Six Sigma roles into two segments:

1. Initiative Leadership
2. Project Leadership

这些细分可以进一步分为六个类别：

1. Six Sigma Executing Leadership or Deployment Leader
2. 六个西格玛冠军
3. 六西格玛大师黑带（MBB）
4. Six Sigma Black Belt (BB)
5. 六个Sigma绿带（GB）
6. Six Sigma Project Team or Yellow Belt (YB)

执行领导，冠军和黑带大师是主动领导的一部分。黑带，绿带和黄色腰带是项目领导力的一部分。

The Champion and Master Black Belt can be part of project leadership and initiative leadership.

Six Sigma Executing Leadership or Deployment Leader

Executing leadership includes project sponsors or top management. They are the ones who establish the business objectives, create the Six Sigma vision for the organization, and make sure everyone understands it.

他们的积极参与是必须实现六个Sigma目标的强制性参与。他们雇用黑带大师，黑带和其他顶级成员，以帮助他们实现组织的目标。

六个西格玛冠军

执行领导选择冠军，他们负责实施六个西格玛。他们管理主黑带，黑带和绿皮带。冠军与这些专业人员合作了解问题并提供支持以解决问题。他们管理整个手术基础的六个Sigma环境。

Champions manage projects from a high level. They can distribute the projects in programs or develop a portfolio to manage them efficiently.

Six Sigma Master Black Belt

冠军选择黑带大师。他们负责project selectionand human resource training. They train Black Belts and Green Belts.

Master Black Belts develop Six Sigma skills within the organization and ensure the sustainability of quality in the project.

他们在项目上推出了六种Sigma方法，并确保活动合规性。他们指导项目团队，如果出现任何问题，可以参与部署领导。

六西格玛黑带

Black Belts execute and implement Six Sigma on the project and are part-time or full-time project team members.

They create the Six Sigma environment and challenge the status quo when there is resistance to implement Six Sigma. They help utilize project resources, mentor the project team that includes Green Belts, and share best practices.

六西格玛绿带s

Green Belts have fewer functions than the Black Belts, they are involved with other project activities besides the Six Sigma activities.

They are sometimes called the “engine” of Six Sigma projects. They are responsible for daily Six Sigma activities, solving issues, calling for help if needed, and ensuring sustainable results.

绿化带负责各自的过程，并有权有效完成工作。这是组织的重要方面，因为绿化带可以在每个过程中建立过程改进结构。

他们在项目执行级别工作，负责六个Sigma结果，并分享最佳实践和经验教训。

Project Team

Project Teams or Yellow Belts include project managers and team members. They are responsible for executing project activities. These people work with Green Belts or Black Belts to achieve the Six Sigma objectives.

These people are subject experts who support Green or Black Belts in developing the process maps and doing data capture for further analysis.

他们不必经过六个Sigma认证，但应该知道六个Sigma功能。

六个Sigma项目的利益相关者

The following are the mainstakeholdersin any Six Sigma project:

• Customer
• Employee
• 供应商
• 最终用户

Six Sigma Methodologies

You can achieve Six Sigma objectives by using two Six Sigma sub-methodologies:

• DMAIC
• DMADV

DMAIC helps you to improve the existing processes incrementally.

DMDAV helps you develop a new process or product. You can also use this methodology with existing processes when you need more than an incremental improvement.

What is DMAIC?

You can use this methodology alone or along with Six Sigma initiatives.

It is a structured problem-solving methodology where each phase depends on the successful completion of the previous one.

DMAIC stands for: Define, Measure, Analyze, Improve, and Control.

Define

在这里，您定义客户及其问题，期望和要求。您可以在过程图的帮助下定义过程，确定改进的领域，定义关键质量（CTQ）特征，设定目标，定义项目界限，并确保必要的资源可用b0b体育app需要。

Measure

Here, you measure the outcome and determine the process’s performance.

You draft a plan to collect reliable data from the process and determine the defects. This data should help you understand performance.

您可以使用客户调查查找缺陷，改进领域或任何功能要求。在此阶段，建立了基线性能。它可以帮助您理解该过程，因此您可以采取进一步的步骤来改进它。

Analyze

Here, you analyze the data collected in the measure-phase and identify the issues that can affect your project or its outcome. You find the gap between the baseline and the current performance. If there is a variation, you find the sources and take corrective action.

您还会寻找任何机会，并利用它们来改善您的项目。

您的主要重点是隔离关键质量特征（CTQ）背后的原因。您还量化解决问题的经济利益。

提升

Once you get to the root cause of the problem, you find a permanent solution and implement it to improve the process.

在这里，您可以研究错误的主要原因，并找到包含它的方法。您可以制定并实施您的新计划和一种新方法，以使缺陷被永久停止。您可以在实施后测量结果。

Control

This phase controls the process for stable performance and prevents the process from reverting to the “old way.” This is an essential phase for lasting results. You monitor the process, ensuring every approved change is implemented and followed.

什么是DMADV？

DMADV可以帮助您开发新的流程或当通过DMAIC的改进不符合客户的期望时使用。

DMADV stands for Define, Measure, Analyze, Design, and Validate.

In both methodologies, DMA is similar; however, the last two letters, “DV,” stand for design and validate.

In the design phase, you create the process or product that fulfills all Critical-to-Quality requirements. In the validate process, you check if all CTQs are as expected and that the final product is meeting or exceeding the customer’s expectations.

The Difference Between DMAIC and DMADV

Both Six Sigma methodologies have the aim of eliminating defects and improving the process, however, there is a difference between how and when you use them.

A few differences are as follows:

• DMAIC用于现有过程，而DMADV则用于新过程。
• DMAIC代表校正，DMADV代表预防。
• In DMAIC, Six Sigma focuses on a few CTQ, while in DMADV, Six Sigma focuses on all possible CTQs.
• DMAIC is usually a shorter duration while DMADV takes a longer time.

Tools Used in Six Sigma

这六个Sigma工具是seven basic quality tools:

1. 理货表
2. 流程图
3. Histograms
4. Cause and Effect Diagram
5. Pareto Diagram
6. 散点图
7. Control Charts

理货表

Thetally sheetis also known as the check sheet or checklist.

使用Tally表，您可以实时记录数据。您转到位置并观察该过程并将其记录在纸上。在大多数情况下，您必须打勾或划掉它。

流程图

Aflow chartis a diagram comprised of boxes connected with lines. This diagram shows you the workflow, process procedure, or algorithm. It helps you visualize the process flow and find issues or bottlenecks.

The flow chart is a useful communication tool and can help you while studying process improvement or documenting a process.

Histogram

Ahistogramis similar to a bar chart and displays the graphical distribution of numerical data. It is primarily used to show frequency distribution.

它可以帮助你发现如果一个过程变化的职业rred from one period to another. A histogram is an excellent communication tool to express data quickly.

Cause and Effect Diagram

This diagram is also known as an Ishikawa or fishbone diagram.

Thecause and effect diagramhelps you find possible causes for a problem. It helps you find bottlenecks in your process, such as why a particular process is not working.

Pareto Diagram

APareto Diagramis a bar chart. The longest bar is on the left side, and the shortest is on the right side. The height of the bar decreases from left to right and the chart displays the frequency of various errors.

You can focus on the most frequently occurring problems with the help of a Pareto Diagram.

散点图

You use two variables in a散点图：一个是因变量，另一个是自变量。

This diagram helps you determine the relationship between the two variables. You can predict the behavior of the other variable after determining the correlation between the two.

Control Charts

Control chartsare used in quality management. These charts let you know if a process is stable.

该图具有均值，较低控制限，上限限制，较低的规范限制和上限限制。

客户设置规范限制和在这些限制之外的任何测量都被视为缺陷。

Advantages of Six Sigma

Six Sigma helps organizations immensely; a few benefits of this methodology include:

1. It is customer-driven.
2. It covers the entire production process rather than just the outcome.
3. 这是一个主动的过程，即使在发现第一个缺陷之前，它也可以帮助您改进过程。
4. It improves quality, eliminates defects, and reduces waste, leading to more satisfied customers, which means more profit and brand recognition.
5. There is a low variation in deliverables.

六西格玛（Six Sigma）通过避免返工，废料，退货成本和售后支持来帮助组织节省资金。

Disadvantages of Six Sigma

There are no inherent disadvantages of this methodology, however, sometimes it may not produce the desired result, or a delay may occur. A few examples of these situations are:

1. 六西格码在生产过程中效果很好，但对研究不起作用（source）。
2. Sometimes, it may create rigid boundaries that could delay the process.
3. Applying it to a small-sized company might be costly.
4. According to some experts, 3.4 defects per million is too low, which may lead to putting more focus on areas with low yield.
5. 如果最高管理不支持，那么六西格玛将不会给出所需的结果。

This was a brief introduction to Six Sigma, and I believe you now have a better understanding of this methodology.

Before I conclude this blog post, let’s discuss the differences between Six Sigma and the PMP certification.

Six Sigma Vs PMP

六西格玛和PMP认证不会相互竞争。两种认证都有不同的目的，尽管在某些时候它们相互互动。

The Six Sigma methodology mainly applies to the manufacturing and financial industries. The PMP methodology applies to all aspects of projects, regardless of industry.

Six Sigma focuses on eliminating defects and reducing waste, and it increases the quality of the product or the process. PMP concentrates on completing the project successfully.

The Six Sigma methodology is forced from top management down to operations, and active involvement from management is mandatory for its successful implementation. With PMP, it is usually individual decisions.

如果您不确定这两项认证，建议您同时选择这两个认证。他们相互补充，可以使您更加高效和就业。

结论

Implementing the Six Sigma methodology involves expense, especially in training and applying changes to the process. However, if implemented, it can bring fruitful results to organizations, such as profitability and brand recognition. The Six Sigma methodology must be implemented and monitored by top management. Their active involvement and support make it successful.

If you are interested in learning Six Sigma, you can join a Six Sigma courses offered by GreyCampus.

• 六西格玛黄色带
• 六西格玛绿带
• Six Sigma Black Belt

（使用优惠券代码PMSC为上述课程获得50％的折扣。）