MSC605 Ch 16

C

A statistical process control chart is allowed to have what percentage of points above the upper control limit or below the lower control limit (if any) and still be considered in control? a. 1% b. 5% c. 0% d. 10%

A

A television manufacturer wants to monitor the proportion of defective television sets that do not meet quality standards from a sample of 100 television sets. In the context of quality control charts, the manufacturer is most likely to use a(n) _____. a. p-chart b. R-chart c. x bar-chart d. s-chart

1:10:100 Rule

If a defect or service error is identified and corrected at the design stage, it might cost $1 to fix. If it is first detected during the production process, it might cost $10 to fix. However, if the defect is not discovered until it reaches the customer, it might cost $100 to correct

A

In determining whether a process is in statistical control, the _____ is always analyzed first. a. R-chart b. p-chart c. x̅-chart d. c-chart

B

In the context of control charts, a process is in control when: a. the control chart has a cyclical pattern. b. all points fall on the center line of the control chart. c. there is a shift in the average value of the process as determined from the control chart. d. the number of points above and below the center line of the control chart is about the same.

?

In the context of control charts, a process is out of control when the control chart: a. has a point outside the control limits. b. shows no shift in the average value of the process. c. shows most points close to or on the center line. d. has an equal number of points above and below the center line

B

In the context of control charts, the _____ is used to control the total number of nonconformances per unit when the size of the sampling unit or number of opportunities for errors is constant. a. R-chart b. c-chart c. x bar-chart d. s-chart

A

In the context of designing control charts, which of the following is true of small sample sizes? a. They are desirable to keep the cost associated with sampling low. b. They allow smaller changes in process characteristics to be detected with higher probability than larger sample sizes. c. They provide more statistical accuracy in estimating the true state of control than larger sample sizes. d. They can accurately detect process shifts of two standard deviations or less.

C

In the context of designing control charts, which statement is true of a sample size? a. A small sample is used to detect process shifts of two standard deviations or smaller. b. A large sample size is desirable to keep the cost associated with sampling low. c. A large sample allows small changes in process characteristics to be detected with higher probability than a small sample size. d. A small sample size provides greater degrees of statistical accuracy in estimating the true state of control than a large sample size.

True

In the context of quality control practices in manufacturing, if supplier documentation is done properly, incoming inspection can be completely eliminated. True/false?

A

In the context of the net promoter score (NPS), scores of 7 or 8 are associated with________, customers who are satisfied but may switch to competitors. a. passives b. promoters c. detractors d. proponents

D

In the context of the net promoter score (NPS), which of the following is a difference between promoters and detractors? a. Unlike promoters, detractors are less price sensitive. b. Unlike promoters, detractors are customers who are associated with scores of 7 or 8. c. Unlike promoters, detractors are satisfied customers who may switch to competitors. d. Unlike promoters, detractors defect at higher rates.

D

In the formula to calculate the process capability index, Cp = (USL-LSL)/σ is used to denote the: a. mean of upper and lower control limits. b. average value of a process. c. total number of nonconformances per unit. d. standard deviation of a process.

A

Overadjusting a process that is in control will: a. increase the variation in the output. b. decrease the proportion of nonconformances in a sample. c. increase the statistical control of the process. d. decrease the cost of repair or service recovery.

C

Select the best Cp score. a. 2 b. 1 c. 6 d. 0

A

Which of the following is a component of a control system? a. A performance standard or goal b. A method for measuring the value of a process c. A chart to monitor the frequency of inventory turnover d. A means of measuring perceived scalability

B

Which of the following is true of a process that is in control? a. A process is in control when special causes are present. b. It does not need any changes or adjustments. c. Overadjusting a process that is in control decreases the variation in the output. d. It does not have any nonconformance due to the lack of common cause variation.

A

Which of the following is true of process capability? a. It has no meaning if a process is not in statistical control as special causes will bias the standard deviation. b. It refers to the exceptional variation in a process that results from assignable causes. c. It should be computed before the elimination of any special causes. d. It is an immeasurable property of a process that allows the qualitative prediction of how the process will meet specifications

C

Which of the following is true of the net promoter score (NPS)? a. It is a metric used to measure employee loyalty. b. It is the difference in the percentage of promoters and passives. c. It is claimed to correlate strongly with market and revenue growth. d. It is evaluated using a six point scale that ranges from 0 to 5.

A

_____ is a methodology for monitoring the quality of manufacturing and service-delivery processes to help identify and eliminate unwanted causes of variation. a. Statistical process control b. Harmonic analysis c. Sequential process control d. Fourier analysis

D

_____ is the result of complex interactions of variations in materials, tools, machines, information, workers, and the environment. a. Special cause variation b. Assignable cause variation c. Exceptional cause variation d. Common cause variation

process capability study

a carefully planned study designed to yield specific information about the performance of a process under specified operating conditions

Statistical process control (SPC)

a methodology for monitoring the quality of manufacturing and service-delivery processes to help identify and eliminate unwanted causes of variation

Special (or assignable) cause variation

arises from external sources that are not inherent in the process, appear sporadically, and disrupt the random pattern of common causes

process capability index

quantifiable relationship between the natural variation and specifications. Ratio of the specification width to the natural variation of the process (Cp)

discrete metric

one that is calculated from data that are counted

continuous metric

one that is calculated from data that are measured as the degree of conformance to a specification on some continuous scale of measurement.

Process Capability

the natural variation in a process that results from common causes

Quality at the source

the people responsible for the work control the quality of their processes by identifying and correcting any defects or errors when they first are recognized or occur.

Common cause variation

the result of complex interactions of variations in materials, tools, machines, information, workers, and the environment