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. Which type of SPC measurement is more precise - variable or attribute?
Variable.
The gap between what management thinks customers want and what customers really want.
10 if Almost impossible to detect
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions

2. Regression
An assertion or conjecture concerning one or more populations
Mean time to replacement.
Represents the behavior of a process
A tool that shows the physical flows through a space.

3. What is FMEA?
Failure Modes and Effects Analysis
Pleasing to the senses.
Define - measure - analyze - design - verify.
Concluding there has been an effect/change when there has not.

4. When yields decrease - what are the two effects on contribution?
Fewer good units to sell - increased variable cost/unit.
The Japanese national quality award.
Taguchi
Different types of defects are listed (used for Pareto chart)

5. In the Service Quality Gap Model - what is Gap 4?
A descending order-sorted bar chart with a cumulative percentage line.
The gap between what is promised and what is delivered.
Used to create frequency distribution tally sheets
Because the mean and standard deviation are independent of each other.

6. What are the four categories of costs in Juran's framework?
Lower skill requirements - faster - less chance for error.
The gap between what is promised and what is delivered.
Speed - courtesy - competence - and ease of repair.
Prevention - appraisal - internal failure - external failure.

7. Process occurance ranking
Linearity - normality - homoscedasticity - independence.
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
It looks to minimize the probability of a failure - or to minimize its effects
Studying firms with the best performance in a particular area.

8. What is muda
The manager in charge of a process being improved in a Six Sigma project.
QFD
Waste.
X-bar-bar

9. Cause and Effect Diagrams
An assertion or conjecture concerning one or more populations
Technical quality is the "what" of the service; functional quality is the "how."
Method developed by Ishikawa to graphically display the causes of any given problem
1) Obtain Residuals 2) Fill out table --> y coordinates: F = 100 (i-.5)/N x coordinates: Ordered Residual 3) Plot on Normal Probability Paper

10. If your process is capable at two sigma - what percentage of the output will be defective (assuming the process is in control)?
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
System to reduce waste and optimize productivity through maintaining an orderly workplace and using visual cues to achieve more consistent operational results.
5%
Financial - customer - internal process - innovation and learning.

11. Define performance quality.
Sort - Set in Order - Shine - Standardize - Sustain
The primary operating characteristics of a product.
The gap between what customers expect and the service they receive.
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.

12. Process check sheets
To manage the Six Sigma project.
5%
Define - measure - analyze - design - verify.
Used to create frequency distribution tally sheets

13. Risk Priority Number RPN
Used to create frequency distribution tally sheets
Quality planning - design review - education and training - process control - IS costs - quality reporting - improvement project costs - working with suppliers before production.
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is
The amount of variation in the dependent variable that is explained by the variation in the independent variable(s).

14. Approximately what percent of a normal distribution falls between ± 3 standard deviations from the mean?
Someone who is consistently against virtually everything.
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality
Prevention and appraisal costs are balanced against internal and external failure.
99.73%

15. F value
F_alpha - df(tr) - df (error)
To manage the Six Sigma project.
Concluding there has not been an effect/change when there has.
A chart that breaks the range of data into equal intervals and then shows the count of occurrences in each interval.

16. Why do you need two control charts for variables SPC?
3.4 (assuming 1.5 sigma shift in the mean)
The gap between what customers expect and the service they receive.
Because the mean and standard deviation are independent of each other.
Represents the behavior of a process

17. What are two other names for an Ishikawa diagram?
Fishbone - cause-and-effect diagram.
10 if Almost impossible to detect
Organize ideas into meaningful categories by recognizing their underlying similarity
Represents the behavior of a process

18. In the Service Quality Gap Model - what is Gap 5?
No -- the variation also has to be random and "expected."
The gap between what customers expect and the service they receive.
Not necessarily.
= S x O x D S--> Severity O--> Occurrence D--> Detection Higher the number the worse it is

19. What is a dashboard?
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
Financial - customer - internal process - innovation and learning.
Walter A. Shewhart
A tool that shows performance along key dimensions all at once.

20. List two components of external failure.
Represent the errors which are random variables with an assumed normal distribution with mean zero and a constant variance σ2.
Complaint adjustment - returned material - warranty charges - allowances - loss of future business.
To do a capability study for a non-centered process.
99.73%

21. Failure effect
Reliability - Assurance - Responsiveness - Tangibles - Empathy
Is the consequence of the failure.
Shifts - Trends - Repeating patterns - Correlation with known events
Technical quality is the "what" of the service; functional quality is the "how."

22. What does DMAIC stand for?
Because the mean and standard deviation are independent of each other.
They move closer to the center line.
Define - measure - analyze - improve - control.
99.73%

23. Daniel Test
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:
Pleasing to the senses.
A descending order-sorted bar chart with a cumulative percentage line.
A tool that shows performance along key dimensions all at once.

24. Uses of regression - Control
Define - measure - analyze - design - verify.
Fishbone - cause-and-effect diagram.
To do a capability study for a non-centered process.
To obtain a certain desirable outcome from the process

25. How does Juran define quality?
The number of standard deviations some value is from the mean.
Lean (or JIT).
Fitness for use.
Define - measure - analyze - improve - control.

26. If a three-stage process has 90% yields at each stage - what is the overall yield?
A brainstorming tool that shows the connections between ideas.
Fractional factorial designs (orthogonal arrays)
0.9^3 or 72.9%
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).

27. Does it ever make sense to accept a job when a process is incapable?
Blame.
To do a capability study for a non-centered process.
Yes - when there are opportunities to improve - when contribution margin is adequate - when achieving market share is important.
If the Response vs. Levels graph if the response lines are not parallel (crossing)

28. What type of risk is associated with Type 1 Error?
Fewer good units to sell - increased variable cost/unit.
Producer risk.
The number of standard deviations some value is from the mean.
Kaoru Ishikawa.

29. Define takt time.
No; if the process is centered - Cp will be the same; if not - Cpk is what you need to determine capabilty.
Waste.
The cycle time required to meet demand.
To obtain a certain desirable outcome from the process

30. Name the structure associated with Quality Function Deployment.
Fishbone - cause-and-effect diagram.
Because the mean and standard deviation are independent of each other.
The House of Quality.
Fractional factorial designs (orthogonal arrays)

31. The Test Statistic (TS)
Supplier - input - process - output - customer.
Failure Modes and Effects Analysis
Can't tell without a Range chart.
A random variable that summarizes the information from the sample(s).

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

33. What type of risk is associated with Type II Error?
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.
Central Limit Theorem
Consumer risk.
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions

34. If a Cp shows that a process is not capable - should you calculate Cpk?
99.73%
A descending order-sorted bar chart with a cumulative percentage line.
No -- if it is not the same - it can only be worse!
False - because each machine will have different natural tolerances.

35. In your major - courses are pass-fail. Would you monitor performance using attribute or variable SPC?
Attribute
Prevention and appraisal costs are balanced against internal and external failure.
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
QFD

36. What is an affinity diagram?
A brainstorming tool that shows the connections between ideas.
99.73%
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).
To mentor/coach (and sometimes train) black belts.

37. What is the formula for standard deviation?
Actual drawings - layouts - maps - etc which show where a defect occurs
A scatterplot.
=sqrt(Σ(x-x-bar)^2)/(n-1))
Reliability - Assurance - Responsiveness - Tangibles - Empathy

38. Simple Regression Analysis (one factor regression model)
= 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
The process of ranking opportunities to determine which of many potential opportunities should be pursued first.
Fishbone - cause-and-effect diagram.
Define - measure - analyze - improve - control.

39. Define aesthetic quality.
95%
The manager in charge of a process being improved in a Six Sigma project.
1) Plot a Line chart of the data in time sequence 2) Draw a line at the median
Pleasing to the senses.

40. Stratified defect check sheets
Stratify a particular defect type according to logical criteria
To be a member of a Six Sigma project team.
Deming.
Blame.

41. 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?
No -- if it is not the same - it can only be worse!
What the value of the dependent variable is when the independent variable is zero.
False - because each machine will have different natural tolerances.
= yij - y(bar)i --> value minus sum of that treatment (of row)

42. Detection Criteria Ranking
The gap between specifications and how service is performed.
Define - measure - analyze - improve - control.
10 if Almost impossible to detect
1) Plot a Line chart of the data in time sequence 2) Draw a line at the median

43. What is process capability?
The target number of standard deviations from the mean for specifications.
The House of Quality.
Sort - Set in Order - Shine - Standardize - Sustain
The ability of a process to consistently meet customer specifications.

44. What are the three main categories of assignable cause?
Performance - features - conformance - reliability - durability - serviceability - aesthetics - perceived quality
Reliability - Assurance - Responsiveness - Tangibles - Empathy
Workers - machines - materials.
Inventory = throughput x flow time.

45. What is CTQ?
Define - measure - analyze - design - verify.
Critical to quality.
Sampling for SPC is done real time.
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.

46. Defect check sheets
Data reduction to put a large number of qualitative inputs into a smaller number of major dimensions
Different types of defects are listed (used for Pareto chart)
Rank of 10 if there is >= 100 per 1000 piece Rank of 1 if there is <=.01 per 1000 pieces
95%

47. Based on what principal can we use the normal distribution assumptions for SPC?
The primary operating characteristics of a product.
Upper control limit.
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
Central Limit Theorem

48. Histogram by Hand
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
Mean time to replacement.
Lower skill requirements - faster - less chance for error.
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

49. List two appraisal costs.
If the Response vs. Levels graph if the response lines are not parallel (crossing)
Vary two or more variables simultaneously - Multiple measurements are obtained under the same experimental conditions
A descending order-sorted bar chart with a cumulative percentage line.
Incoming materials inspection - inspection and testing - maintaining test equipment - materials/services consumed

50. Explain the difference between technical and functional service quality.
Technical quality is the "what" of the service; functional quality is the "how."
Concluding there has been an effect/change when there has not.
Supplier - input - process - output - customer.
Fishbone - cause-and-effect diagram.