Chapter 1

process capability indices

Another set of measures exist to quantify the capability of a process or characteristics to meet its specifications. These indices directly compare the voice of the process to the voice of the customer.

black belt

Black Belts are the heart and soul of the Six Sigma quality initiative. Their main purpose is to lead quality projects and work full time. As team leaders, Black Belts use project tracking and management tools as well as process optimization. Black Belts can typically complete four to six projects per year with savings of approximately $230,000 per project. Black Belts also coach Green Belts on their project.

functional analysis diagram

Identifies and organizes the important functions of a process or product.

pareto principle

The principle explains that 80% of the effects come from relatively few causes; that is, 80% of the effects come from 20% of the possible causes.

what phase of DMAIC uses FMEA

improve

trend/ run chart

trend or the run charts primarily focuses the changing trend or pattern over a specified period of time before measuring the performance of a process.

SIPOC

-Acronym for supplier, input, process, output, customer -Used in define phase of DMAIC -Made to define the sub processes in major business process Categorizing the process Categorizing the outputs Defining the outputs by their name, title, or organizational entity Defining the customer requirements Defining the inputs Categorizing the sources of the inputs

Affinity diagrams

-Affinity diagrams are used to show the representation of brainstormed ideas -The Affinity diagram helps to organize the unorganized data and refine the output of the brainstorming session.

histogram

-Histograms are used as a graphic tool to display continuous occurrence of data values and attempt to show the number of times a value has occurred most frequently and least frequently. -Frequency distribution -"Histograms are defined as bar graph of a frequency distribution in which the widths of the bars are proportional to the classes into which the variable has been divided and the heights of the bars are proportional to the class frequencies

green belt

Green Belts are employees trained in Six Sigma who spend a portion of their time completing projects, but maintain their regular work routine and responsibilities. Depending on their workload, they may spend 10% to 50% of their time on their projects. They operate under the guidance of Black Belts and support them in achieving the overall results. Green Belts use similar tools as Black Belts with a lower level of analytical prowess.

Measure

In this stage, the existing systems are measured. The potential critical processes/products are identified and described.

T-test

a statistical test used to evaluate the size and significance of the difference between two means

fishbone

as the name suggests, the Fishbone diagram looks like a fish with the head identifying the specific problem of interest, and the six bones identifying six categories comprising of "five Ms and one E". They are Measurements, Materials, Men, Methods, Machines, and Environment.

operational definitions

definitions that state specifically how to measure the defined item, or how to interpret data or events in a process.

multi-vari chart

is used to display a pattern of variation. It is used to identify the causes of variations, such as variations between a subgroup.

statistical significance of a result

probability that the observed relationship or a difference in a sample occurred by pure chance, and that in the population from which the sample was drawn, no such relationship or differences exist.

line graphs

shows changes over a period of time or compares the relationship between two quantities

Multivoting

-follow-up to brainstorming - These meaningful and organized sets of ideas are further arranged in an order of importance including common problems and causes. The list may comprise of 3-5 items. Each member of the group is allowed to rank each item of importance. Thus, the item, which receives the highest number of ranking from the group, is considered for further analysis.

Force field diagram

-helps in the understanding of the driving forces that work towards the process of improvement and restraining forces that block any improvement or change taking place. -used to compare opposites, actions, consequences, and different point of views.

Failure Mode and Effect Analysis (FMEA)

A procedure and tools that help to identify every possible failure mode of a process or product, to determine its effect on other sub-items and on the required function of the product or process

Chi square test

A significance test used to determine if a linear relationship exists between two variables measured on interval or ratio scales.

Three types of tree diagrams or hierarchical diagrams

-cause and effect diagrams -y to x flowdown diagrams -functional analysis diagrams

cause and effect diagram

The Cause and Effect diagram is used to brainstorm possible causes of a problem or effects. It puts the possible causes into groups, and reviews the causes that lead to other causes

Define phase

The Define Phase comprises of base lining and benchmarking the process that needs improvement. Further goals/sub-goals are specified and the infrastructure to accomplish these goals is established. An assessment of changes in the organization is also taken into consideration.

y to x tree diagram

The Y-to-X Tree Diagram helps in the identification and classification of the factors (independent variables) that may drive an important results variable. It helps to recognize the factors (Xs) that may drive changes in the results variable Y.

Structured tree

The brainstormed ideas are presented with links in a hierarchical fashion in the structure tree. The structure tree shows how goals and solutions to the problems presented in the brainstormed ideas can be connected using a structure tree.

defect rate

The complimentary measurement of yields is defects. If the yield is 90 percent, naturally there must be 10 percent defects.

master black belt

acts as the in-house expert coach for the organization. They see that the overall Six Sigma initiatives are accountable to the executives and the operational business units. They are full time agents to Six Sigma. They assist champions, and guide Black Belts and Green Belts. Apart from the usual routine, they spend their time on ensuring integrated deployment of Six Sigma across various functions and departments.

Analysis of Variance (ANOVA)

analyzing data that tests for a difference between two or more means by comparing the variances *within* groups and variances *between* groups."

Regression

enables you to quantify the relationship between two or more variables (X) and (Y) by fitting a line or plane through all the points such that they are evenly distributed about the line or plane

checksheets

forms, which are used to collect and organize data. Checksheets can be simple tables, surveys, or diagrams, to point out where errors might have occurred.

yield

Traditionally, yield is the proportion of correct items you get out of a process compared to the number of raw items you put into it.

control chart

Control charts are primarily used in the control phase of the DMAIC process. It is defined as a graphical tool for monitoring changes that occur within a process because of some common cause. Control charts help to show the trends in the average or the variation, which further helps in the debugging process. A control charts consists of a run chart, centerline and upper and lower limits determined statistically.

DMADV methodology

D- define project goals consistent with customer demand M-Measure and determine customer needs and specifications -Analyze the process options to meet the customer needs and design alternatives D- Design the process to meet customer needs V-Verify the design performance and ability to meet customer needs

Defects per unit

DPU provides a measurement of the average number of defects on a single unit

Improvement Phase

In this phase the improvement project teams are composed to provide Six Sigma project-related training to the team members. As the progression of the projects take place, it is important to constantly monitor the status of each project.

Analyze phase

In this phase, the gaps are identified between current process performance and the business goals. The gaps are further transformed into improvement projects, and an integrated system is established to support the implementation.

Improve

In this stage, the improved outcome is measured to determine whether the revised method produces results within customer expectations.

Control

In this stage, the new system is controlled and the original problems are stopped from recurring.

Analyze

In this stage, the system is to be analyzed to identify ways to eliminate the gap between the current performance of the system or process and the desired goal.

scatter plot

This graphic tool is used to search for direct relationship between two factors in a process, to see if a correlation exists between the two. It does not show cause and effect

Flowchart

This pictorial view usually depicts the inputs, outputs, and the unit of activity in a process. It analyzes and observes the process from its initiation to its completion. A flowchart is mostly presented in the form of a diagram comprising of boxes, diamonds, and other shapes, and these boxes are connected with arrows. Each box or a shape represents a step in the process and each arrow shows the order of the activities that are performed.