Test your basic knowledge |

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. In the Service Quality Gap Model - what is Gap 1?
Prediction and estimation. based on an unknown x value - estimation is based on a known x value
The gap between what management thinks customers want and what customers really want.
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"

2. Process occurance ranking
Outside.
Look for the assignable cause of non-random variation.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
Organize ideas into meaningful categories by recognizing their underlying similarity

3. Pareto Analysis
To mentor/coach (and sometimes train) black belts.
False - because each machine will have different natural tolerances.
3.4 (assuming 1.5 sigma shift in the mean)
The process of ranking opportunities to determine which of many potential opportunities should be pursued first.

4. An SPC chart shows no points outside the control limits. Does this mean the process is in control?
p-bar - the long-run percent defective.
The secondary characteristics of a product; "bells and whistles."
Lower control limit.
No -- the variation also has to be random and "expected."

5. Failure effect
100%
Is the consequence of the failure.
Large enough to find two of the attribute - on average.
Through producer/consumer negotiation.

6. What happens to control limits on an SPC chart when sample size is increased?
A time series plot.
50%
100%
They move closer to the center line.

7. One factor at a time (OFAT)
Observed variation in response is caused by the input
Lower control limit.
Hold all input variables constant except one. Observe the response as you vary the single input.
Can't tell without a Range chart.

8. Statistical Hypothesis
If the Response vs. Levels graph if the response lines are not parallel (crossing)
Linearity - normality - homoscedasticity - independence.
Blame.
An assertion or conjecture concerning one or more populations

9. Define performance quality.
The gap between what management thinks customers want and what customers really want.
The primary operating characteristics of a product.
Look for the assignable cause of non-random variation.
A chart that breaks the range of data into equal intervals and then shows the count of occurrences in each interval.

10. Advantages of DOE
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.
Inventory = throughput x flow time.
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
Consumer risk.

11. Your production process meets customer specifications. Is your process in control?
Not necessarily.
Prevention - appraisal - internal failure - external failure.
Technical quality is the "what" of the service; functional quality is the "how."
Scrap - rework - retest - downtime - yield losses - disposition costs.

12. Define features.
No -- the variation also has to be random and "expected."
The secondary characteristics of a product; "bells and whistles."
The ratio of outputs to inputs; 1-scrap.
95%

13. What does the abbreviation UCL stand for?
Upper control limit.
To be a member of a Six Sigma project team.
What the value of the dependent variable is when the independent variable is zero.
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper

14. FMEA
= y = Beta(0) + Beta(1)X + epsilon y=dependent variable (response) x=independent variable (predictor of y) - epsilon=error component - Beta(not)=intersection. If data include zero - it represents the mean of the distribution of y when - x=0. It does
3.4 (assuming 1.5 sigma shift in the mean)
How much variance you expect around the prediction; two SEs gives you a 95% confidence interval.
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

15. In the Service Quality Gap Model - what is Gap 3?
The target number of standard deviations from the mean for specifications.
Prevention and appraisal costs are balanced against internal and external failure.
An interaction is defined as a dependence relationship between the response and the levels of two or more variables
The gap between specifications and how service is performed.

16. DOE
Outside.
The cycle time required to meet demand.
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
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan

17. Who developed the fishbone diagram?
Kaoru Ishikawa.
Central Limit Theorem
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.
To mentor/coach (and sometimes train) black belts.

18. Definition of Interaction
A random variable that summarizes the information from the sample(s).
An interaction is defined as a dependence relationship between the response and the levels of two or more variables
False - because each machine will have different natural tolerances.
Kaoru Ishikawa.

19. What quality guru emphasizes management as a system?
Deming.
Scrap - rework - retest - downtime - yield losses - disposition costs.
A time series plot.
X-bar-bar

20. Which quality guru developed the concept of loss to society?
QFD
Define - measure - analyze - design - verify.
Is the consequence of the failure.
Taguchi

21. What is the center line of a p-chart?
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions
p-bar - the long-run percent defective.
Outside.
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

22. Failure Mode
The manager in charge of a process being improved in a Six Sigma project.
Is the way in which the failure is manifested.
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
A random variable that summarizes the information from the sample(s).

23. When either attribute or variable measures could be used for SPC - why might attribute measurement be preferred?
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
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
Mistake-proofing.
Lower skill requirements - faster - less chance for error.

24. Manual Test for Nomality
No -- if it is not the same - it can only be worse!
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).
Conformance to specifications.
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper

25. Uses of regression
Prediction and estimation. based on an unknown x value - estimation is based on a known x value
Concluding there has not been an effect/change when there has.
Fewer good units to sell - increased variable cost/unit.
Reliability - Assurance - Responsiveness - Tangibles - Empathy

26. A process is operating "in control." Does this mean the customer's requirements are met?
To manage the Six Sigma project.
Rapid improvement process.
Lean is waste reduction - Six Sigma is variation reduction.
No -- only if the process is also capable.

27. What type of risk is associated with Type II Error?
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
Technique used to relate through a model - one or more independent variables and a dependent variable (response)
Consumer risk.
50%

28. What is the formula for the standard deviation of a proportion?
=sqrt((p*(1-p)/n)
Prevention and appraisal costs are balanced against internal and external failure.
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed
Actual drawings - layouts - maps - etc which show where a defect occurs

29. In Juran's Cost of Quality model - which categories of costs balance which other categories?
A tools that is used to measure the amount of variation in the measurement system arising from the measurement device (repeatability) and the people taking the measurement (reproducibility).
Not necessarily.
99.73%
Prevention and appraisal costs are balanced against internal and external failure.

30. Explain the difference between technical and functional service quality.
Technical quality is the "what" of the service; functional quality is the "how."
Supplier - input - process - output - customer.
Waste.
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

31. Based on what principal can we use the normal distribution assumptions for SPC?
Central Limit Theorem
To obtain a certain desirable outcome from the process
Mistake-proofing.
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions

32. What is poka yoke?
Mean time to failure.
Mistake-proofing.
Brand image.
3.4 (assuming 1.5 sigma shift in the mean)

33. What type of risk is associated with Type 1 Error?
Producer risk.
Brand image.
68%
An assertion or conjecture concerning one or more populations

34. What is Jidoka?
Controlling quality at the source.
Producer risk.
The manager in charge of a process being improved in a Six Sigma project.
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

35. In the Service Quality Gap Model - what is Gap 2?
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"
Technique used to relate through a model - one or more independent variables and a dependent variable (response)
The gap between what management thinks customers want and the process specifications.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces

36. What is the difference between the way sampling is done for SPC and for acceptance sampling?
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
Variable.
Sampling for SPC is done real time.
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. Simple Regression Analysis (one factor regression model)
Prediction and estimation. based on an unknown x value - estimation is based on a known x value
A descending order-sorted bar chart with a cumulative percentage line.
= y = Beta(0) + Beta(1)X + epsilon y=dependent variable (response) x=independent variable (predictor of y) - epsilon=error component - Beta(not)=intersection. If data include zero - it represents the mean of the distribution of y when - x=0. It does
Upper control limit.

38. List Garvin's eight dimensions of product quality.
Taguchi
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality
Before production starts
A descending order-sorted bar chart with a cumulative percentage line.

39. Process check sheets
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan
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).
Used to create frequency distribution tally sheets
Critical to quality.

40. What is DPMO?
Defects Per Million Opportunities
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
What the value of the dependent variable is when the independent variable is zero.
The number of standard deviations some value is from the mean.

41. Define takt time.
The cycle time required to meet demand.
A brainstorming tool that shows the connections between ideas.
Lower skill requirements - faster - less chance for error.
10 for Hazardous without warning 1 for none

42. Define perceived quality (Garvin's framework).
Rapid improvement process.
Brand image.
Workers - machines - materials.
If the Response vs. Levels graph if the response lines are not parallel (crossing)

43. Stratified defect check sheets
Sampling for SPC is done real time.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
Stratify a particular defect type according to logical criteria
Defects Per Million Opportunities

44. What is Type 1 Error?
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
Concluding there has been an effect/change when there has not.
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
Waste.

45. Does it ever make sense to accept a job when a process is incapable?
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.
A tool that shows performance along key dimensions all at once.
Can't tell without a Range chart.
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan

46. F value
F_alpha - df(tr) - df (error)
No -- the variation also has to be random and "expected."
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions
Producer risk.

47. Define serviceability.
Concluding there has been an effect/change when there has not.
Speed - courtesy - competence - and ease of repair.
Look for the assignable cause of non-random variation.
A tools that is used to measure the amount of variation in the measurement system arising from the measurement device (repeatability) and the people taking the measurement (reproducibility).

48. What do you do when a process is out of control?
Pleasing to the senses.
Lean is waste reduction - Six Sigma is variation reduction.
Look for the assignable cause of non-random variation.
No -- only if the process is also capable.

49. What is process capability?
Causes that lead to a particular effect.
= yij - y(bar)i --> value minus sum of that treatment (of row)
Conformance to specifications.
The ability of a process to consistently meet customer specifications.

50. What is written on the "spines" of a fishbone diagram?
Scrap - rework - retest - downtime - yield losses - disposition costs.
An assertion or conjecture concerning one or more populations
Causes that lead to a particular effect.
What the value of the dependent variable is when the independent variable is zero.