Six Sigma Basic Questions – 5 Sets of 20 Questions
Set 1 (20 Questions)-
1. DMAIC stands for “Define, Measure, Analyze, Integrate, Control”. True or false?
2. In a Gage R&R, the “R&R” stands for reliability and reproducibility. True or false?
3. W. Edwards Deming is often described as the father of modern quality control. He is well known for the PDCA cycle. What does this acronym stand for?
4. A dependent variable (“Y”) drives the performance of an independent variable (“X”). True or false?
5. The Kano model is a technique typically used to identify the hidden factory in a process. True or false?
6. What is the formula for DPMO?
7. Which of these does a Project Champion typically not do?
a) Defines projects
b) Breaks down roadblocks
c) Helps obtain resources
d) Provides technical Six Sigma expertise.
8. The Kano model is a technique to understand how well products or services meet customer needs. True or false?
9. The term “FMEA” stands for
a) Failure Mode and Effects Analysis
b Failure Methods and Engineering Analysis
c) Failure Mode and Enhancement Appraisal
d) Final Model of Engineering Analysis
10. A run chart is used to analyze attribute data. True or false?
11. A Fishbone diagram, a Cause and Effect Diagram and an Ishikawa diagram are all different names for the same visual analytical tool. True or false?
12. A Gage R&R is a form of Measurement System Analysis. True or false?
13. What is the formula for sample standard deviation?
14. A useful rule of thumb in hypothesis testing is that if the P value is under 0.05%, the null hypothesis should be accepted. True or false?
15. What is a Yamazumi Chart? Explain in 50 words or less.
16. A Type I error is taking action when it is not needed (false positive); a Type II error is not taking action when you should have done (false negative). True or false?
17. Root cause analysis, Pareto diagrams and Y=f(x) analysis are most commonly associated with the Control phase. True or false?
18. Which of these does a Black Belt typically not do?
a) Applies kaizen thinking for continuous improvement
b) Line manages the improved process once implemented
c) Uses analytical tools to identify the root causes of problems
d) Personally leads Six Sigma projects
19. In a box plot, the line in the middle of the box is the median. True or false?
20. Which major US company embraced Six Sigma in the 1990s and helped bring it to widespread attention?
a) Goldman Sachs
b) General Electric
c) General Motors
d) Blue Star Airlines
Congratulations on completing the test. The answers are below.
Answers – Set 1
1. False. DMAIC stands for “Define, Measure, Analyze, Improve, Control”
2. False. The R&R stands for “Repeatability” and “Reproducibility”
3. PDCA stands for Plan — Do — Check — Act.
4. False. An independent variable (“X”) drives the performance of a dependent variable (“Y”).
5. False. The Kano model is a customer satisfaction model.
6. DPMO is typically defined as Defect/ (Units * Opportunities), all multiplied by 1 million.
7. d) Provides technical Six Sigma expertise. A Project Manager is normally a business person. Six Sigma “profound knowledge” (Deming) is the preserve of the Black Belt or Master Black Belt.
9. a) Failure Modes and Effects Analysis
10. A run chart is used to analyse variable data.
11. True. These are all names for the same type of chart.
12. True. A Gage R&R tests the effectiveness of your measurement system.
13. The formula for sample standard deviation is best explained on Wikipedia.
14. False. The reverse is true. “If the p is low, the null must go” i.e. the null hypothesis should be rejected.
15. Yamazumi charts are explained here.
16. True. The question is a little clumsy but is correct. Technically, a Type I error is incorrectly rejecting the null hypothesis (an error of commission); a Type II error is failing to reject the null hypothesis when you should have done so (an error of omission).
17. False. These are most commonly associated with the introductory phases (Define – Measure – Analyze) of a project, although clearly they may be used at any point.
18. b) A Six Sigma Black Belt will not normally take over line management responsibility for an improved process on an ongoing basis. He or she will be on to the next project!
19. True. Boxplots are explained here.
20. b) General Electric. Jack Welch was a strong advocate of Six Sigma.
Set 2 (20 Questions)-
1. What Is the Cost of Poor Quality?
2. What is the 1.5 sigma shift?
3. A Green Belt is attempting to improve the customer experience provided by a call centre for a budget airline ( telephone support). As a result he should build a list of Critical to Quality Characteristics based on ____________________.
a. Service benefits defined by customers
b. Product features requested by customers
c. Cost of production
d. Size of unit
e. The Voice of the Business
4. What questions should I use to prepare for a Six Sigma tollgate review?
5. What statistical software program should I use to analyze data?
6. A dairy learned through a Lean Six Sigma project their ice cream products could be stored at a temperature 2 degrees higher than they had historically used. Since their energy costs for ice cream storage cost $6,000 per month per degree of temperature, what was reported as the annual savings from this LSS project?
7. Producing more than is needed by the next step in the process or more than the customer needs is an example of which of the Seven Elements of Waste?
b. Correction (defects)
8. An FMEA is an important tool for a Black Belt. From the list below select the three items that best describe the benefits obtained from constructing a FMEA.
a. Predict where/when/how failures may occur
b. Estimate the severity, occurrence and detection of defects
c. Helps display the procedural order of a process
d. Identify ways in which a process can fail to meet customer requirements
e. Identify which 20 % of causes of defects are responible for approx 80% of all defects
9. The shape of a Normal Distribution is impacted primarily by:
a. Sample Error
c. Data Type
d. The standard deviation or variance of the data distribution
10. Since 95% of Normally Distributed data is within +/- 2 Standard Deviations of the Mean, then the probability is _____% that a sample Mean is within +/- 2 Standard Deviations of the population Mean.
11. After running some statistical tests, a Belt found that the P-value was greater then 0.05 which indicated:
a. There is a difference or relationship with at least 95% confidence
b. There is no difference or relationship with at least 95% confidence
c. To reject the Null Hypothesis with a least 95% confidence
d. To run five more tests to get 95% confidence
e. To change the Null Hypothesis
12. Which of the following statements is false of the Pareto Chart Effects diagram output
shown by Minitab above?
a. There are 5 factors varied in this experimental effort.
b. Factor “B” has the highest effect on the output measured in this experiment.
c. Three-Way interaction effects have a significant effect on the output.
d. Factor “C” has the lowest main effect on the output measured in this experiment.
e. Two-Way interactions and Main effects are to be pursued in further trials.
13. Which item is the least descriptive of a properly designed control system using the Lean toolbox?
a. Balanced and consistent work flow across a process
b. Zero inventory of Work In Process (WIP)
c. Tidy, organized and maintained office equipment or machinery
d. Labeled inventory areas which control the production of material or services
14 A characteristic of properly executed SPC includes which of the following (Select two answers):
a. Immediate response to an out of control indication
b. After a action to an out of control indication of violating the 3 sigma limits, the next data point is just within the 3 sigma limits so another action was taken to further reduce the response
c. Plotting the response from the process at the end of the day and then analyzing for out of control conditions and taking actions if still out of control
d. Creation of Out of Control Action Plans before using an SPC Chart in the process
15. If unsustained results are the case after project closure, what actions should be taken to recapture the benefits of the Six Sigma project?
a. Contact the Belt no matter where he/she is
b. Contact the Belt if still in the same process area
c. Reference the Control Plans and key finding in the final report
d. Check to see if the SPC Charts are up to date
16. The 5S approach to removing waste is part of the application of Lean and is comprised
of Sorting, Straightening, Sharpening, Standardizing and Sustaining.
17. A Kanban is used as a part of the ____________________ portion of Lean to assure
the proper amount of inventory and appropriate timing of inventory flow through a
a. Visual Factory
b. Kaizen Event
d. Shakowa Analysis
18. As a Belt completes a LSS project she creates for the Process Owner a Control Plan. The
Control Plan is to remain active and open for __________________.
a. One year
b. The rest of the fiscal year
c. The life of the process
d. Three years
19. During the Process Discovery activity of the Measure Phase our team uses a
___________________ to brainstorm concerning all the potential things that could
impact the output of the process we are investigating.
a. Pareto Chart
b. Shewhart Analytical
c. Fishbone Diagram
20. To properly evaluate a process we must gather and analyze key metric data impacting
that process. To assure the data we analyze is accurate and precise we must begin its
collection by creating a ____________________.
a. Data Definition Chart
b. Database Collection System
c. Measurement System Analysis
Congratulations on completing the test. The answers are below.
Answers: Set 2
1. COPQ includes:
Those costs generated as a result of producing defective material.
The cost involved in fulfilling the gap between the desired and actual product or service quality.
The cost of lost opportunity due to the loss of resources used in fixing the defect, including all the labor cost, rework cost, disposition costs and material costs that have been added to the unit up to the point of rejection.
A portion of the appraisal cost if there is an inspection point.
COPQ does not include detection and prevention cost.
2. After a process has been improved using the Six Sigma DMAIC methodology, we calculate the process standard deviation and sigma value. These are considered to be short-term values because the data only contains common cause variation — DMAIC projects and the associated collection of process data occur over a period of months, rather than years. Long-term data, on the other hand, contains common cause variation and special (or assignable) cause variation. Because short-term data does not contain this special cause variation, it will typically be of a higher process capability than the long-term data. This difference is the 1.5 sigma shift. Given adequate process data, you can determine the factor most appropriate for your process.
In Six Sigma, The Breakthrough Management Strategy Revolutionizing The World’s Top Corporations, Harry and Schroeder write:
“By offsetting normal distribution by a 1.5 standard deviation on either side, the adjustment takes into account what happens to every process over many cycles of manufacturing… Simply put, accommodating shift and drift is our ‘fudge factor,’ or a way to allow for unexpected errors or movement over time. Using 1.5 sigma as a standard deviation gives us a strong advantage in improving quality not only in industrial process and designs, but in commercial processes as well. It allows us to design products and services that are relatively impervious, or ‘robust,’ to natural, unavoidable sources of variation in processes, components, and materials.”
Statistical Take Away: The reporting convention of Six Sigma requires the process capability to be reported in short-term sigma – without the presence of special cause variation. Long-term sigma is determined by subtracting 1.5 sigma from our short-term sigma calculation to account for the process shift that is known to occur over time.
3. A -Service benefits
4. Project Review Agenda-
a. Introduction by Project Champion or Sponsor-
This would allow the Champion to set the stage for the review, as well as highlight the importance of the project.
b. Project Team Presentation-
By determining the level of formality prior to the meeting, the team will know if questions will be reserved until the end or if they should prepare to be interrupted. In the presentation, a quick summary of previous reviews should be presented, but the bulk of the time should be spent on the recently completed project phase.
c. Reviewer Comments (if formal presentation, otherwise this is intertwined with #2)-
Reviewers should now identify the positive work the team has completed on the current phase, both in their logic and utilization of the tools to achieve the current results. Clarification questions and suggestions for the team to consider should also be presented at this time. If the team did not properly use a tool or did not extract the proper information from a tool, it is appropriate to postpone sign-off of the phase. The sign-off authority may be granted to the Master Black Belt once certain requirements are met.
d. Closing by Project Champion or Sponsor-
As with the introduction, the Champion – who has the most to gain or lose from the project – will set the stage for the project going forward. Encouragement and support is always a necessary ingredient for success.
5. Many Tools available –
Web-based Six Sigma enterprise quality management solutions.
Statistical analysis software for Microsoft Excel, including histograms, linear and polynomial regression, ANOVA, chi-square and more.
Web-based portal for Six Sigma program and project management, including an integrated set of tools, training, references and roadmap.
Minitab Statistical Software
Statistical data analysis package for quality improvement, DOE, Gage R&R, general statistics and more.
Find more at https://www.isixsigma.com/six-sigma-software/
6. B – $144,000
7. A – Overproduction
8. A – Predict where/when/how failures may occur
B – Estimate the severity, occurrence and detection of defects
D – Identify ways in which a process can fail to meet customer requirements
9. D- The Standard Deviation or Variance of the data Distribution
10. D – 95%
11. B – There is no difference or relationship with at least 95% confidence
12. C- Three-Way interaction effects have a significant effect on the output. ( is incorrect)
13. B- Zero inventory of Work In Process (WIP)
14. A- Immediate response to an out of control indication
D Creation of Out of Control Action Plans before using an SPC Chart in the
15. C- Reference the Control Plans and key finding in the final report
16. B False
17. A Visual Factory
18. C The life of the process
19. C Fishbone Diagram
20. C Measurement System Analysis
More Questions and Answers to come.…….. Please share