1. As we discussed in class, common cause variation is best considered:
a. Controllable at the source of the variation.
b. Called assignable cause as it is something that is periodic, yet common.
c. Can be reduced by statistical process control methods
d. The responsibility of the operator in charge on the production line. e. The responsibility of management overseeing the production line.
2. Testing whether a cellphone boots up the first time 100% correctly is an example of:
a. Supplier certification and management.
b. In-process control.
c. Finished goods control.
d. Statistical process control.
e. None of the above.
3. Which of the following is not related to a continuous metric?
a. Measured as the degree of conformance to a specification
b. x-bar and R-charts
c. p-chart d. Time
e. n-charts
4. Honda wants to monitor the number of blemishes (scratches, blisters, etc.) on the fenders of its cars using a statistical process control chart. The most appropriate type of SPC chart is:
a. X-bar.
b. R-bar chart.
c. CpK chart.
d. C-chart.
e. Q-chart
5. In the context of designing control charts, which of the following is true of a sample size?
a. A large sample allows small changes in process characteristics to be detected with higher probability than a small sample size.
b. A small sample is used to detect process shifts of two standard deviations or smaller.
c. A large sample size is desirable to keep the cost associated with sampling low.
d. A small sample size provides greater degrees of statistical accuracy in estimating the true state of control than a large sample size.
e. A small sample allows for medium-sized changes in process characteristics to be detected with a stationary probability than a small sample size.
6. Which of the following is true of special cause variation?
a. It cannot be explained or understood
b. It occurs sporadically and can be prevented.
c. It cannot be detected using statistical methods.
d. It accounts for about 80 to 95 percent of the observed variation in a process.