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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. Define durability.
The amount of variation in the dependent variable that is explained by the variation in the independent variable(s).
Mean time to replacement.
Taguchi
The secondary characteristics of a product; "bells and whistles."

2. What does DMAIC stand for?
No -- if it is not the same - it can only be worse!
Define - measure - analyze - improve - control.
Blame.
Inventory = throughput x flow time.

3. 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?
Lower skill requirements - faster - less chance for error.
Organize ideas into meaningful categories by recognizing their underlying similarity
False - because each machine will have different natural tolerances.
The House of Quality.

4. Complete this quality phrase: 'Fix the process - not the _____.'
The degree to which a product meets pre-established standards.
Blame.
The US national quality award.
99.73%

5. What is a spaghetti diagram?
An interaction is defined as a dependence relationship between the response and the levels of two or more variables
A tool that shows the physical flows through a space.
It looks to minimize the probability of a failure - or to minimize its effects
The secondary characteristics of a product; "bells and whistles."

6. Taguchi's experimental designs are of this type.
Fractional factorial designs (orthogonal arrays)
Walter A. Shewhart
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed
A brainstorming tool that shows the connections between ideas.

7. Uses of regression - Control
The gap between what is promised and what is delivered.
Walter A. Shewhart
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan
To obtain a certain desirable outcome from the process

8. Your production process meets customer specifications. Is your process in control?
Method developed by Ishikawa to graphically display the causes of any given problem
Not necessarily.
Lean is waste reduction - Six Sigma is variation reduction.
Speed - courtesy - competence - and ease of repair.

9. Defect location check sheets
The gap between specifications and how service is performed.
Actual drawings - layouts - maps - etc which show where a defect occurs
Variable.
Defects Per Million Opportunities

10. Residual(eij)
A scatterplot.
= yij - y(bar)i --> value minus sum of that treatment (of row)
Lower skill requirements - faster - less chance for error.
50%

11. Failure Mode
F_alpha - df(tr) - df (error)
The ratio of outputs to inputs; 1-scrap.
Is the way in which the failure is manifested.
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.

12. In the Service Quality Gap Model - what is Gap 3?
The amount of variation in the dependent variable that is explained by the variation in the independent variable(s).
A diagram that shows the relationships between activities in a project network.
Scrap - rework - retest - downtime - yield losses - disposition costs.
The gap between specifications and how service is performed.

13. Affinity Diagrams
Organize ideas into meaningful categories by recognizing their underlying similarity
The gap between what customers expect and the service they receive.
Speed - courtesy - competence - and ease of repair.
Deming.

14. What is DPMO?
Define - measure - analyze - design - verify.
Defects Per Million Opportunities
Define - measure - analyze - improve - control.
Blame.

15. What graphical tool is used to show the relationship between two numerical variables?
A descending order-sorted bar chart with a cumulative percentage line.
A scatterplot.
Prevention - appraisal - internal failure - external failure.
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality

16. DFMEA
Initiated before or at design concept finalization
Inventory = throughput x flow time.
Supplier - input - process - output - customer.
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.

17. ANOVA

18. For what is an x-bar chart used?
Method developed by Ishikawa to graphically display the causes of any given problem
Producer risk.
5%
To monitor a process when measurement by variables is used.

19. Risk Priority Number RPN
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.
Someone who is consistently against virtually everything.
Rapid improvement process.
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is

20. For your SPC sample you weigh bags of potatoes. Is this variable or attribute SPC?
A brainstorming tool that shows the connections between ideas.
Upper control limit.
Is what induces the failure
Variable.

21. What is the formula for the standard deviation of a proportion?
Brand image.
=sqrt((p*(1-p)/n)
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"
Walter A. Shewhart

22. List two appraisal costs.
A descending order-sorted bar chart with a cumulative percentage line.
Waste.
Upper control limit.
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

23. What is the 5S model?
A brainstorming tool that shows the connections between ideas.
What the value of the dependent variable is when the independent variable is zero.
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.
Lean is waste reduction - Six Sigma is variation reduction.

24. What is a Pareto chart?
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
How much variance you expect around the prediction; two SEs gives you a 95% confidence interval.
100%
A descending order-sorted bar chart with a cumulative percentage line.

25. In the Service Quality Gap Model - what is Gap 1?
It looks to minimize the probability of a failure - or to minimize its effects
Critical to quality.
The gap between what management thinks customers want and what customers really want.
The secondary characteristics of a product; "bells and whistles."

26. Uses of regression
Prediction and estimation. based on an unknown x value - estimation is based on a known x value
Brand image.
A tool that shows where there is waste in a process.
The cycle time required to meet demand.

27. What is the difference between Lean and Six Sigma?
It's good -- but it's still out of control!
Lean is waste reduction - Six Sigma is variation reduction.
Linearity - normality - homoscedasticity - independence.
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper

28. List two components of internal failure.
99.73%
A tool that shows the physical flows through a space.
Fewer good units to sell - increased variable cost/unit.
Scrap - rework - retest - downtime - yield losses - disposition costs.

29. What is the difference between the way sampling is done for SPC and for acceptance sampling?
No -- only if the process is also capable.
Reliability - Assurance - Responsiveness - Tangibles - Empathy
Sampling for SPC is done real time.
Someone who is consistently against virtually everything.

30. To what does the Six in Six Sigma relate?
Critical to quality.
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper
The target number of standard deviations from the mean for specifications.
A random variable that summarizes the information from the sample(s).

31. What is the formula for standard deviation?
To monitor a process when measurement by attribute is used.
Look for the assignable cause of non-random variation.
The gap between what management thinks customers want and the process specifications.
=sqrt(Σ(x-x-bar)^2)/(n-1))

32. What is an affinity diagram?
A brainstorming tool that shows the connections between ideas.
Through producer/consumer negotiation.
The number of standard deviations some value is from the mean.
Assigns scores to weighted criteria for each project under consideration.

33. What is Little's Law?
Inventory = throughput x flow 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
The gap between specifications and how service is performed.
X-bar-bar

34. What inventory approach contributes to process quality by "lowering the river to find the rocks?"
Observed variation in response is caused by the input
Outside.
No -- if it is not the same - it can only be worse!
Lean (or JIT).

35. What are the three main categories of assignable cause?
A simple graph between two variables - visualize the type - degree of strength and shape of the relationship between two variables
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
It looks to minimize the probability of a failure - or to minimize its effects
Workers - machines - materials.

36. DOE
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 time series plot.
Shifts - Trends - Repeating patterns - Correlation with known events
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.

37. With Six Sigma capability - how many defects per million opportunities would you see?
Before production starts
3.4 (assuming 1.5 sigma shift in the mean)
To do a capability study for a non-centered process.
Variable.

38. Explain the difference between technical and functional service quality.
Failure Modes and Effects Analysis
Define - measure - analyze - improve - control.
Financial - customer - internal process - innovation and learning.
Technical quality is the "what" of the service; functional quality is the "how."

39. Who is a process owner?
The manager in charge of a process being improved in a Six Sigma project.
Central Limit Theorem
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

40. Which quality guru developed the concept of loss to society?
Someone who is consistently against virtually everything.
Taguchi
Not necessarily.
Consumer risk.

41. For what is a p-chart used?
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
QFD
To monitor a process when measurement by attribute is used.
Scrap - rework - retest - downtime - yield losses - disposition costs.

42. Creating a Run Chart
1) Plot a Line chart of the data in time sequence 2) Draw a line at the median
Consumer risk.
The secondary characteristics of a product; "bells and whistles."
=sqrt((p*(1-p)/n)

43. How are LQL and AQL determined in an acceptance sampling plan?
Through producer/consumer negotiation.
Look for the assignable cause of non-random variation.
Conformance to specifications.
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

44. Stratified defect check sheets
Method developed by Ishikawa to graphically display the causes of any given problem
A diagram that shows the relationships between activities in a project network.
It looks to minimize the probability of a failure - or to minimize its effects
Stratify a particular defect type according to logical criteria

45. What size should samples be for attribute SPC?
Large enough to find two of the attribute - on average.
To manage the Six Sigma project.
Stratify a particular defect type according to logical criteria
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.

46. If your process is capable at two sigma - what percentage of the output will be defective (assuming the process is in control)?
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan
No -- only if the process is also capable.
The amount of variation in the dependent variable that is explained by the variation in the independent variable(s).
5%

47. Test for constant variance
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.
=sqrt(Σ(x-x-bar)^2)/(n-1))
Causes that lead to a particular effect.
Used to create frequency distribution tally sheets

48. In the Service Quality Gap Model - what is Gap 4?
Mistake-proofing.
What the value of the dependent variable is when the independent variable is zero.
How much variance you expect around the prediction; two SEs gives you a 95% confidence interval.
The gap between what is promised and what is delivered.

49. The Test Statistic (TS)
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.
A brainstorming tool that shows the connections between ideas.
A random variable that summarizes the information from the sample(s).
Technique used to relate through a model - one or more independent variables and a dependent variable (response)

50. Define perceived quality (Garvin's framework).
The gap between what customers expect and the service they receive.
The number of standard deviations some value is from the mean.
Brand image.
Producer risk.