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Six Sigma

Subjects : certifications, six-sigma, business-skills

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. List two components of internal failure.
Define - measure - analyze - design - verify.
Scrap - rework - retest - downtime - yield losses - disposition costs.
Fitness for use.
The House of Quality.

2. When yields decrease - what are the two effects on contribution?
Because the mean and standard deviation are independent of each other.
To be a member of a Six Sigma project team.
Fewer good units to sell - increased variable cost/unit.
The degree to which a product meets pre-established standards.

3. What is the role of a master black belt?
0.9^3 or 72.9%
Assigns scores to weighted criteria for each project under consideration.
It's good -- but it's still out of control!
To mentor/coach (and sometimes train) black belts.

4. What type of risk is associated with Type II Error?
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
Fractional factorial designs (orthogonal arrays)
The ability of a process to consistently meet customer specifications.
Consumer risk.

5. One factor at a time (OFAT)
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
68%
Observed variation in response is caused by the input
Speed - courtesy - competence - and ease of repair.

6. Who first studied randomness in industrial processes
Walter A. Shewhart
Taguchi
Is what induces the failure
Central Limit Theorem

7. Does it ever make sense to accept a job when a process is incapable?
Prevention and appraisal costs are balanced against internal and external failure.
No -- if it is not the same - it can only be worse!
The gap between what customers expect and the service they receive.
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.

8. There are two milling machines in the shop. Data has been collected on one to compute control limits for both. This is acceptable SPC practice - true or false and why?
False - because each machine will have different natural tolerances.
Attribute.
Technical quality is the "what" of the service; functional quality is the "how."
10 for Hazardous without warning 1 for none

9. Based on what principal can we use the normal distribution assumptions for SPC?
Mean time to replacement.
Not necessarily.
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
Central Limit Theorem

10. If a three-stage process has 90% yields at each stage - what is the overall yield?
A tool that shows where there is waste in a process.
0.9^3 or 72.9%
Fewer good units to sell - increased variable cost/unit.
The US national quality award.

11. For what is an x-bar chart used?
Prevention - appraisal - internal failure - external failure.
Mistake-proofing.
To monitor a process when measurement by variables is used.
The primary operating characteristics of a product.

12. Test for Independence
If the Response vs. Levels graph if the response lines are not parallel (crossing)
The gap between specifications and how service is performed.
consists of plotting the residuals vs. the order of each experiment - If - as in the case of the constant variance a random horizontal band is obtained - the ______________ of the residuals is not rejected. (should be random above a below the line i
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.

13. Residual(eij)
= yij - y(bar)i --> value minus sum of that treatment (of row)
No -- the variation also has to be random and "expected."
How likely it is to have an F statistic of that value if there really is no relationship between the dependent variable and the independent variable(s).
Linearity - normality - homoscedasticity - independence.

14. What happens to control limits on an SPC chart when sample size is increased?
Rapid improvement process.
They move closer to the center line.
Observed variation in response is caused by the input
To do a capability study for a non-centered process.

15. TWO-DIMENTIONAL SCATTER PLOT
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.
A simple graph between two variables - visualize the type - degree of strength and shape of the relationship between two variables
To mentor/coach (and sometimes train) black belts.
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

16. If your process is capable at two sigma - what percentage of the output will be defective (assuming the process is in control)?
X-bar-bar
5%
Sort - Set in Order - Shine - Standardize - Sustain
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

17. Failure effect
Is the consequence of the failure.
How likely it is to have an F statistic of that value if there really is no relationship between the dependent variable and the independent variable(s).
Actual drawings - layouts - maps - etc which show where a defect occurs
False - because each machine will have different natural tolerances.

18. If you have calculated a Cpk - should you also calculate a Cp?
Waste.
Taguchi
Fishbone - cause-and-effect diagram.
No; if the process is centered - Cp will be the same; if not - Cpk is what you need to determine capabilty.

19. Daniel Test
An assertion or conjecture concerning one or more populations
Attribute
Another way to assess the significance of the analyzed factors is through a graphic procedure developed by C. Daniel when only one replicate (a single observation) was obtained:
The US national quality award.

20. What is muda
Fitness for use.
Outside.
Waste.
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions

21. In Juran's Cost of Quality model - which categories of costs balance which other categories?
1.Interactions can be detected and measured 2.Each value does the work of several values 3.Experimental error is quantified and used to determine the confidence the experimenter has in the conclusions
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
No -- if it is not the same - it can only be worse!
Prevention and appraisal costs are balanced against internal and external failure.

22. Affinity Diagrams
Waste.
To do a capability study for a non-centered process.
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.
Organize ideas into meaningful categories by recognizing their underlying similarity

23. Approximately what percent of a normal distribution falls between ± 1 standard deviations from the mean?
consists of plotting the residuals vs. the order of each experiment - If - as in the case of the constant variance a random horizontal band is obtained - the ______________ of the residuals is not rejected. (should be random above a below the line i
It looks to minimize the probability of a failure - or to minimize its effects
A scatterplot.
68%

24. Define aesthetic quality.
The House of Quality.
Plot the residuals vs. the fitted values (mean of each group - y(hat) = y (bar)i ) - Assumption of ____________not rejected if the dispersion of every group is approximately the same.
The degree to which a product meets pre-established standards.
Pleasing to the senses.

25. What is the center line of a p-chart?
Inventory = throughput x flow time.
A scatterplot.
p-bar - the long-run percent defective.
A diagram that shows the relationships between activities in a project network.

26. What are the Five Dimensions of Service Quality?
A tool that shows where there is waste in a process.
Variable.
Reliability - Assurance - Responsiveness - Tangibles - Empathy
A simple graph between two variables - visualize the type - degree of strength and shape of the relationship between two variables

27. Risk Priority Number RPN
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is
A systemized group of activities designed to 1. recognize and evaluate the potential failure of product/process and its effects 2. Identify actions which could eliminate or reduce the chance of potential failure ocurring 3. document the process
10 if Almost impossible to detect

28. Uses of regression
Prediction and estimation. based on an unknown x value - estimation is based on a known x value
Speed - courtesy - competence - and ease of repair.
Large enough to find two of the attribute - on average.
Defects Per Million Opportunities

29. In your major - courses are pass-fail. Would you monitor performance using attribute or variable SPC?
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.
The gap between what customers expect and the service they receive.
Attribute
Outside.

30. Defect location check sheets
Actual drawings - layouts - maps - etc which show where a defect occurs
A tool that shows performance along key dimensions all at once.
Is the consequence of the failure.
68%

31. What is a spaghetti diagram?
Fewer good units to sell - increased variable cost/unit.
Prevention - appraisal - internal failure - external failure.
Upper control limit.
A tool that shows the physical flows through a space.

32. One factor at a time (OFAT)
Look for the assignable cause of non-random variation.
Prevention and appraisal costs are balanced against internal and external failure.
No -- if it is not the same - it can only be worse!
Hold all input variables constant except one. Observe the response as you vary the single input.

33. Manual Test for Nomality
A scatterplot.
Plot the residuals vs. the fitted values (mean of each group - y(hat) = y (bar)i ) - Assumption of ____________not rejected if the dispersion of every group is approximately the same.
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper
QFD

34. What is Kaizen?
To do a capability study for a non-centered process.
A diagram that shows the relationships between activities in a project network.
Is what induces the failure
Rapid improvement process.

35. Regression Analysis
Variable.
Technique used to relate through a model - one or more independent variables and a dependent variable (response)
99.73%
Inventory = throughput x flow time.

36. An SPC chart shows no points outside the control limits. Does this mean the process is in control?
Central Limit Theorem
No -- the variation also has to be random and "expected."
It usually isn't possible to hold all other variables constant - There is no way to account for the effect of joint variation of independent variables - such as interaction - There is no way to account for experimental error - including measurement v
Decomposing the total variation of data into: (a) the internal or "natural" or "within" groups variation - and (b) the "between" groups variation in such a way that when these two types of variation are compared - it's possible to determine if there

37. For your SPC sample you weigh bags of potatoes. Is this variable or attribute SPC?
Because the mean and standard deviation are independent of each other.
Variable.
The target number of standard deviations from the mean for specifications.
The gap between what customers expect and the service they receive.

38. What is the formula for the standard deviation of a proportion?
Kaoru Ishikawa.
= yij - y(bar)i --> value minus sum of that treatment (of row)
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.
=sqrt((p*(1-p)/n)

39. What is the role of a black belt?
Conformance to specifications.
Variable.
To manage the Six Sigma project.
A tool that shows performance along key dimensions all at once.

40. What is the Baldrige Award?
Is the way in which the failure is manifested.
Organize ideas into meaningful categories by recognizing their underlying similarity
The US national quality award.
Shows the temporal flow of activities in a project network.

41. Define product reliability.
68%
99.73%
Organize ideas into meaningful categories by recognizing their underlying similarity
Mean time to failure.

42. Affinity Diagrams
Kaoru Ishikawa.
Producer risk.
Data reduction to put a large number of qualitative inputs into a smaller number of major dimensions
Studying firms with the best performance in a particular area.

43. What does SIPOC stand for?
Mistake-proofing.
Supplier - input - process - output - customer.
The House of Quality.
Plot the residuals vs. the fitted values (mean of each group - y(hat) = y (bar)i ) - Assumption of ____________not rejected if the dispersion of every group is approximately the same.

44. What are the four regression assumptions?
Technical quality is the "what" of the service; functional quality is the "how."
Linearity - normality - homoscedasticity - independence.
To obtain a certain desirable outcome from the process
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality

45. What does DMAIC stand for?
Taguchi
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper
Define - measure - analyze - improve - control.
No -- if it is not the same - it can only be worse!

46. If your process is capable at two sigma - what percentage of the output will you have to inspect to find defectives?
10 for Hazardous without warning 1 for none
=sqrt((p*(1-p)/n)
100%
1) Plot a Line chart of the data in time sequence 2) Draw a line at the median

47. Who is a process owner?
The manager in charge of a process being improved in a Six Sigma project.
It looks to minimize the probability of a failure - or to minimize its effects
Fishbone - cause-and-effect diagram.
F_alpha - df(tr) - df (error)

48. What is an affinity diagram?
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan
A brainstorming tool that shows the connections between ideas.
1) Identify the Range (Max Value - Min Value) 2) Determine # of bins 3) Determine the Width of each bin --> (Range / # Bins) 4) Put values in correct Bin
Workers - machines - materials.

49. When either attribute or variable measures could be used for SPC - why might attribute measurement be preferred?
Studying firms with the best performance in a particular area.
Lower skill requirements - faster - less chance for error.
The primary operating characteristics of a product.
The gap between what customers expect and the service they receive.

50. In the Service Quality Gap Model - what is Gap 3?
The gap between specifications and how service is performed.
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.
95%
Inventory = throughput x flow time.