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. Failure cause
Causes that lead to a particular effect.
Linearity - normality - homoscedasticity - independence.
Someone who is consistently against virtually everything.
Is what induces the failure

2. Why do you need two control charts for variables SPC?
68%
Because the mean and standard deviation are independent of each other.
10 for Hazardous without warning 1 for none
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

3. In the Service Quality Gap Model - what is Gap 1?
The number of standard deviations some value is from the mean.
The gap between what management thinks customers want and what customers really want.
Technical quality is the "what" of the service; functional quality is the "how."
Is what induces the failure

4. What inventory approach contributes to process quality by "lowering the river to find the rocks?"
Pleasing to the senses.
Lean (or JIT).
A descending order-sorted bar chart with a cumulative percentage line.
The cycle time required to meet demand.

5. Residual
Lean (or JIT).
No; if the process is centered - Cp will be the same; if not - Cpk is what you need to determine capabilty.
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
Shows the temporal flow of activities in a project network.

6. Explain the difference between technical and functional service quality.
The cycle time required to meet demand.
Taguchi
Mean time to failure.
Technical quality is the "what" of the service; functional quality is the "how."

7. What size should samples be for attribute SPC?
Large enough to find two of the attribute - on average.
No -- the variation also has to be random and "expected."
Speed - courtesy - competence - and ease of repair.
The gap between what customers expect and the service they receive.

8. In a regression - what does the standard error of the estimate tell you?
A random variable that summarizes the information from the sample(s).
The gap between what is promised and what is delivered.
68%
How much variance you expect around the prediction; two SEs gives you a 95% confidence interval.

9. List two components of external failure.
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
A time series plot.
Represents the behavior of a process
Look for the assignable cause of non-random variation.

10. Detection Criteria Ranking
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"
A scatterplot.
10 if Almost impossible to detect
0.9^3 or 72.9%

11. Define serviceability.
A chart that breaks the range of data into equal intervals and then shows the count of occurrences in each interval.
An assertion or conjecture concerning one or more populations
Speed - courtesy - competence - and ease of repair.
Outside.

12. What are the 5 Ss?
A simple graph between two variables - visualize the type - degree of strength and shape of the relationship between two variables
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
Stratify a particular defect type according to logical criteria
Sort - Set in Order - Shine - Standardize - Sustain

13. What percentage of a normal distribution lies above the mean?
The number of standard deviations some value is from the mean.
50%
A time series plot.
99.73%

14. Regression Analysis
QFD
Central Limit Theorem
Because the mean and standard deviation are independent of each other.
Technique used to relate through a model - one or more independent variables and a dependent variable (response)

15. In a regression - what does the coefficient of the intercept tell you
68%
What the value of the dependent variable is when the independent variable is zero.
A time series plot.
Is the consequence of the failure.

16. In the Service Quality Gap Model - what is Gap 2?
Lean is waste reduction - Six Sigma is variation reduction.
The gap between what management thinks customers want and the process specifications.
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:
Look to your customer - not to other firms. "You can always find someone shorter - fatter and balder!"

17. Define takt time.
Supplier - input - process - output - customer.
Linearity - normality - homoscedasticity - independence.
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
The cycle time required to meet demand.

18. Advantages of DOE
Attribute
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
Walter A. Shewhart
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

19. What are the three main categories of assignable cause?
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is
No -- the variation also has to be random and "expected."
p-bar - the long-run percent defective.
Workers - machines - materials.

20. For what is an x-bar chart used?
To monitor a process when measurement by variables is used.
To monitor a process when measurement by attribute is used.
Controlling quality at the source.
A simple graph between two variables - visualize the type - degree of strength and shape of the relationship between two variables

21. Approximately what percent of a normal distribution falls between ± 1 standard deviations from the mean?
Shows the temporal flow of activities in a project network.
68%
The House of Quality.
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

22. What is poka yoke?
Mean time to replacement.
Mistake-proofing.
The ability of a process to consistently meet customer specifications.
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan

23. What does DMAIC stand for?
Define - measure - analyze - improve - control.
Shows the temporal flow of activities in a project network.
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is
Pleasing to the senses.

24. Residual(eij)
QFD
= yij - y(bar)i --> value minus sum of that treatment (of row)
0.9^3 or 72.9%
The degree to which a product meets pre-established standards.

25. Statistical Hypothesis
A tool that shows performance along key dimensions all at once.
50%
Through producer/consumer negotiation.
An assertion or conjecture concerning one or more populations

26. Define durability.
Rapid improvement process.
Mean time to replacement.
Reliability - Assurance - Responsiveness - Tangibles - Empathy
Linearity - normality - homoscedasticity - independence.

27. What quality tool formally incorporates the voice of the customer?
The secondary characteristics of a product; "bells and whistles."
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality
An assertion or conjecture concerning one or more populations
QFD

28. Define conformance quality.
Large enough to find two of the attribute - on average.
Is what induces the failure
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
The degree to which a product meets pre-established standards.

29. You have been plotting sample means on an x-bar chart and all points indicate normal - expected variation. Is the process in control?

30. What is muda
Taguchi
Is the consequence of the failure.
Waste.
Pleasing to the senses.

31. What is a spaghetti diagram?
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper
A scatterplot.
50%
A tool that shows the physical flows through a space.

32. One factor at a time (OFAT)
If the Response vs. Levels graph if the response lines are not parallel (crossing)
Observed variation in response is caused by the input
100%
Through producer/consumer negotiation.

33. What type of risk is associated with Type 1 Error?
Prevention - appraisal - internal failure - external failure.
Lean (or JIT).
Producer risk.
Sampling for SPC is done real time.

34. Define product reliability.
Speed - courtesy - competence - and ease of repair.
Prevention - appraisal - internal failure - external failure.
Mean time to failure.
Technical quality is the "what" of the service; functional quality is the "how."

35. ANOVA

36. What is Type 1 Error?
Lean is waste reduction - Six Sigma is variation reduction.
Concluding there has been an effect/change when there has not.
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
A descending order-sorted bar chart with a cumulative percentage line.

37. If a Cp shows that a process is not capable - should you calculate Cpk?
Workers - machines - materials.
The gap between specifications and how service is performed.
To do a capability study for a non-centered process.
No -- if it is not the same - it can only be worse!

38. Affinity Diagrams
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).
0.9^3 or 72.9%
They move closer to the center line.
Organize ideas into meaningful categories by recognizing their underlying similarity

39. What is DPMO?
Is the way in which the failure is manifested.
Defects Per Million Opportunities
Fractional factorial designs (orthogonal arrays)
Different types of defects are listed (used for Pareto chart)

40. What is a histogram?
Used to create frequency distribution tally sheets
Initiated before or at design concept finalization
Not necessarily.
A chart that breaks the range of data into equal intervals and then shows the count of occurrences in each interval.

41. If you have calculated a Cpk - should you also calculate a Cp?
It's good -- but it's still out of control!
No; if the process is centered - Cp will be the same; if not - Cpk is what you need to determine capabilty.
Studying firms with the best performance in a particular area.
Lower control limit.

42. If a three-stage process has 90% yields at each stage - what is the overall yield?
0.9^3 or 72.9%
= yij - y(bar)i --> value minus sum of that treatment (of row)
5%
F_alpha - df(tr) - df (error)

43. Affinity Diagrams
Data reduction to put a large number of qualitative inputs into a smaller number of major dimensions
The ratio of outputs to inputs; 1-scrap.
The secondary characteristics of a product; "bells and whistles."
Consumer risk.

44. What is a network diagram?
A diagram that shows the relationships between activities in a project network.
The ability of a process to consistently meet customer specifications.
Taguchi
Concluding there has not been an effect/change when there has.

45. List Garvin's eight dimensions of product quality.
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality
Lower skill requirements - faster - less chance for error.
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
No -- the variation also has to be random and "expected."

46. Non-random patterns (Run Charts)
Shifts - Trends - Repeating patterns - Correlation with known events
Organize ideas into meaningful categories by recognizing their underlying similarity
The secondary characteristics of a product; "bells and whistles."
A diagram that shows the relationships between activities in a project network.

47. With Six Sigma capability - how many defects per million opportunities would you see?
Pleasing to the senses.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
The House of Quality.
3.4 (assuming 1.5 sigma shift in the mean)

48. How are LQL and AQL determined in an acceptance sampling plan?
Through producer/consumer negotiation.
To monitor a process when measurement by variables is used.
5%
An experiment where one or more variables believed to have an effect on an experimental outcome are identified and manipulated according to a plan

49. When yields decrease - what are the two effects on contribution?
The target number of standard deviations from the mean for specifications.
Fewer good units to sell - increased variable cost/unit.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
Mean time to failure.

50. What are the four perspectives of the Balanced Scorecard?
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
A tool that shows where there is waste in a process.
Financial - customer - internal process - innovation and learning.
If the Response vs. Levels graph if the response lines are not parallel (crossing)