Six Sigma and Statistical Process Control: Key Concepts
78) Which step of the Six Sigma DMAIC procedure monitors the process to make sure high performance levels are maintained?
E) Control
79) Which step of the Six Sigma DMAIC procedure involves identifying data sources and preparing a data collection plan?
B) Measure
80) Six Sigma teachers can attain different level titles, based on their experience and level of achievement. What is the highest level a Six Sigma teacher can reach?
C) Master Black Belt
81) In acceptance sampling, the proportion defective that the buyer will allow in an incoming shipment is:
D) The acceptable quality level (AQL).
82) In acceptance sampling, when the random sample passes the buyer’s incoming test (low number of defects found), the next action taken is to:
A) Accept the entire lot of incoming materials.
83) Which of the following would be a “common” cause of variation?
A) Random sources
84) Which one of the following statements is TRUE?
A) Nothing can be done to completely eliminate variation in process output.
85) In Statistical Process Control, ________ are used to detect defects and determine if the process has deviated from design specifications.
D) Control Charts
86) A sampling plan is best for evaluating quality when:
Inspection costs are high + Destructive testing is required
87) A measure of the dispersion of observations in a process distribution is called a(an):
B) Range.
88) Which of the following can be used to eliminate “common” causes of variation?
D) They cannot be eliminated.
89) Which one of the following statements about quality control is TRUE?
A) Measurement by attributes is a simple yes or no decision.
90) Which one of the following statements relating to quality is TRUE?
C) The distribution of sample means can be approximated by the normal distribution.
91) When should complete inspection be used?
C) When the cost of product failure is high relative to the inspection costs
92) An operator of a filling machine plotted the weights of each bag she filled for three weeks. At the same time, a quality inspector’s sampling distribution will:
B) Have less variability than the operator’s.
93) In SPC, the distribution of sample means:
A) Can be approximated by the normal distribution.
94) The three sigma limits for a process whose distribution conforms to the normal distribution include approximately:
D) 99% of the observed values in the long run.
95) Regarding control charts, a type I error refers to concluding that the process is:
C) Out of control when it is in control.
96) An example of a type I error would be:
A) Throwing away a perfectly good banana.
97) An example of a type II error would be:
C) Eating food that you were unaware was spoiled.
98) Regarding control charts, changing from three-sigma limits to two-sigma limits:
B) Increases the probability of searching for a cause when none exists.
99) Regarding control charts, changing from two-sigma limits to three-sigma limits:
A) Increases the probability of concluding nothing has changed, when in fact something has changed.
100) The UCL and LCL for an
chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 24, and 16. What should you do?
A) Nothing; the process is in control.
101) The central line on a p-chart is 0.50 with a UCL of 0.65 and an LCL of 0.35. The results of the next six samples are 0.60, 0.37, 0.45?
C) Explore assignable causes because there is a run.
102) The underlying statistical distribution for the p-chart is:
B) Binomial