Six Sigma Definitions

• Define
• Measure
• Analyze
• Improve
• Control

• Define design goals
• Measure and identify CTQ's.
• Analyze to develop and design alternatives
• Design details (play for verification/simulations)
• Verify the design (setup pilot runs and implement)

Monitors variance in a process over time and alerts the business to unexpected variance which may cause defects.

Based on the proven Pareto principle: 20% of the sources cause 80% of any problems. Focuses on efforts or the problems that have the greatest potential for improvement. Created by Vilfredo Pareto an italian economist.

Attributes most important to the customer

Failing to deliver what the customer wants. May not always mean a failure.

How widely spread the variation of your measurement system is compared to the actual. This goes towards reproducability or repeatability.

This shows how centered your MSA is with the actual variation of the process. A stable MSA that is accurate os one that stays centered and free of changes.

Defined as 3.4 defects per million opportunities

Dividing data into groups (strata) based on key characteristics. Typically these are:

• * People
• * Process step
• * Product/Service
• * Machines/Equipment
• * Location
• * Suppliers
• * Time/Day
• * Suppliers

In Six Sigma it is usually used in the expression of Y=f(X), where the output (Y) is a function of the inputs (X).

Average of all of the values

Japanese term that means "mistake-proof"

Defective Parts Per Million

Defects Per Million Opportunities

Value observed most frequently

20-20-21-7-3-5-7-20 would be 20

Difference between the largest and the smallest data values.

• r = x_min - x_max
• 2-4-6-7-10 would be 10-2 or 8

This is the point where half of the data points are over the line and half are below it.

1,2,3,8,9,12,16 is 8... if the number is odd then the two numbers are divided.

• Voice of the process - is it stable?
• Voice of the customer - is it capable?

Capability is how well the voice of your process matches up with the VOC and how it meets their customer expectations.

A standard against which measurements or comparisons can be made.

Analysis of Variance: A statistical test for identifying significant differences between process or system treatments or conditions. It is done by comparing the variances around the means of the conditions being compared.

The costs associated with any activity that is not doing the right thing right the first time. It is the financial qualification of any waste that is not integral to the product or service.

The best demonstrated performance for an existing configuration of a process or system. It is an empirical demonstration of what level of improvement can potentially be reached.

Failure Mode and Effects Analysis (FMEA) - A procedure used to identify, assess, and mitigate risks associated with potential product, system, or process failure modes.

A measure that is considered to be a key indicator of performance. It should be linked to goals or objectives and carefully monitored.

A decision making method for use among groups of many sizes, who want to make their decision quickly, as by a vote, but want everyone's opinions taken into account. Usually introduction and explanation occurs, then silent generation of ideas, then sharing ideas, group discussion, and voting and ranking of those ideas.

Quality Function Deployment (QFD) - A systematic process used to integrate customer requirements into every aspect of the design and delivery of products and services.

Risk Priority Number (RPN) - In Failure Mode Effects Analysis, the aggregate score of a failure mode including its severity, frequency of occurrence, and ability to be detected.

Rolled Throughput Yield (RTY) - The probability of a unit going through all process steps or system characteristics with zero defects.

An acronym used to describe a method to determine the validity of customer requirements. It stands for reasonable, understandable, measurable, believable, and achievable.

Voice of the Business (VOB) - Represents the needs of the business and the key stakeholders of the business. It is usually items such as profitability, revenue, growth, market share, etc.