Operations Management - Chapter 9, Operations Management Chapter 10, Operations Management - Chapter 10
High Quality and low prices are both considered to be dimensions of quality.
FALSE
ISO standards apply only to manufacturing organizations.
FALSE
If the majority of service customers are satisfied, it is likely that all service customers will be satisfied.
FALSE
In market research, a group of consumers who express their opinions about a product or service is called a steering committee.
FALSE
Juran describes quality management as a trilogy that consists of quality planning, control of quality costs, and quality improvement.
FALSE
A quality circle is a cross-functional team focused on quality.
FALSE
An organization achieves quality by consistently meeting their competitor's standards.
FALSE
Because 'courtesy' is subjective, it can't be considered a factor in service quality.
FALSE
Broadly defined, quality refers to the ability of a product or service to occasionally meet or exceed customer expectations.
FALSE
Continuous improvement attempts to achieve major breakthroughs in product or service quality.
FALSE
Cost of inspectors, testing, test equipment, and labs are examples of prevention costs.
FALSE
Deming stresses that workers are primarily responsible for poor quality because very often they fail to follow instructions.
FALSE
The tool that is useful in documenting the current process is: A. a control chart B. a Pareto chart C. a check sheet D. a flow chart E. a simo chart
D. a flow chart
The primary purpose of statistical process control is to detect a defective product before it is shipped to a customer.
FALSE The primary purpose of SPC is to detect nonrandomness.
An x-bar control chart can only be valid if the underlying population it measures is a normal distribution.
FALSE The sample average typically is normally distributed regardless of the underlying distribution of the process.
Low-cost, high-volume items often require more intensive inspection.
FALSE These are not good candidates for inspection.
Type I and Type II errors refer to the magnitude of variation from the standard.
FALSE These refer to decisions regarding whether the process is in or out of control.
Approving the effort that occurs during the production process is known as acceptance sampling.
FALSE Acceptance sampling occurs before or after the production process.
According to Deming, it is the systems that management puts into place that are primarily responsible for poor quality, not employees.
TRUE
Business organizations achieving good quality benefit in a variety of ways, including a positive reputation for quality, increased customer loyalty, and lower production costs.
TRUE
Convenience, Reliability and Assurance are dimensions of service quality.
TRUE
Cost of inspectors, testing, test equipment, and labs are examples of appraisal costs.
TRUE
Crosby's concept of "quality is free" means that it is less expensive to do it right initially than to do it over.
TRUE
Customer expectations tend to change over time affecting their perception of service quality.
TRUE
Firms that wish to do business with the European Community can benefit from having a quality management system that meets ISO 9000 standards.
TRUE
ISO standards aid in transferring technology to developing countries.
TRUE
Juran describes quality management as a trilogy that consists of quality planning, quality control, and quality improvement.
TRUE
Medical malpractice claims are an example of how poor quality can affect an organization through liability.
TRUE
One criticism of total quality management is that it may produce blind pursuit of quality to the neglect of other priority considerations.
TRUE
Process mapping is part of process improvement.
TRUE
Quality of conformance refers to the degree to which goods and services conform to the intent of the designers as documented in the specifications.
TRUE
Recent changes to ISO guidelines stress continuous improvement regardless of how good you currently are.
TRUE
Reducing the variations in our product or service is an important key to perceived quality.
TRUE
Serviceability, Conformance and Reliability are dimensions of product quality.
TRUE
Six sigma programs have both management and technical components.
TRUE
TQM expands the traditional view of quality beyond looking only at the quality of the final product or service to looking at the quality of every aspect of the process.
TRUE
TQM is not just a collection of techniques. It is rather a whole new attitude toward quality.
TRUE
The PDSA cycle forms the conceptual basis for continuous improvement.
TRUE
The customer is the focal point and customer satisfaction is the driving force in quality management.
TRUE
The degree to which a product or service satisfies its intended purpose is determined by service after delivery, ease of use, design, and conformance to design.
TRUE
The dimensions of product and service quality are too abstract to be applied operationally.
TRUE
The primary difference between internal failures and external failures is time and place of discovery of the failure.
TRUE
The purpose of benchmarking is to establish a standard against which the organization's performance can be judged, and to identify a model for possible improvement.
TRUE
There is a positive link between quality and productivity.
TRUE
Three key philosophies in TQM are continuous improvement, involvement of everyone in the organization, and customer satisfaction.
TRUE
Total quality management attempts to involve everyone in an organization in the effort to achieve quality.
TRUE
User instructions and follow-up services after delivery are important elements of overall product or service quality.
TRUE
When considering service quality, convenience often is a major factor.
TRUE
"Quality of conformance" is concerned with whether a product or service conforms to its specifications.
TRUE Specification conformance is quality of conformance.
The amount of inspection needed is governed by the costs of inspection and the expected costs of passing defective items.
TRUE These interact to set the optimum amount of inspection.
The sampling distribution can be assumed to be approximately normal even when the underlying process distribution is not normally distributed.
TRUE This is especially true as the sample size grows.
Modern quality management emphasizes finding and correcting mistakes before they reach the customer - catching the errors before they are shipped.
FALSE
One of the major obstacles to implementing TQM is the emphasis on long-term financial results.
FALSE
Poor quality has a positive effect on productivity because it usually takes longer to produce a good part.
FALSE
Product design choices are usually the result of inputs from accounting and human resources.
FALSE
Quality at the source means returning all defects to the source - our vendors.
FALSE
The degree to which a product or service satisfies its intended purpose is determined by design, conformance to design, cost, and reputation of the producer.
FALSE
An "up and down" run test uses the median as a reference point and measures the percentage above and below the median.
FALSE An up-and-down runs test looks only at runs of increasing or decreasing values.
The purpose of statistical process control is to ensure that historical output is random.
FALSE It is to ensure that non-random variation is detected and corrected.
Larger samples will require wider x-bar control limits because there is more data.
FALSE Large samples will lead to narrower control limits.
A control chart is a visual representation of the various states in a process.
FALSE
A tool used to organize data into logical categories is called a(n) ___. A. Affinity diagram B. Check list C. Control Chart D. Flow Chart E. Relationship diagram
A. Affinity diagram
_______ variation is a variation whose cause can be identified. A. Assignable B. Controllable C. Random D. Statistical E. Theoretical
A. Assignable Assignable variation has a special cause.
A chart showing the number of occurrences by category would be used in: A. Pareto analysis B. interviewing C. cause-and-effect diagrams D. benchmarking E. none of the above
A. Pareto analysis
The Baldrige award is based on seven categories. Which is not one of those? A. Relative profitability B. Strategic planning C. Human resource focus D. Information and Analysis E. Leadership
A. Relative profitability
Lost production time, scrap, and rework are examples of ___. A. internal failure costs B. external failure costs C. appraisal costs D. prevention costs E. replacement costs
A. internal failure costs
A control chart used to monitor the fraction of defectives generated by a process is the: A. p-chart B. R-chart C. x-bar chart D. c-chart E. Gantt chart
A. p-chart The p-chart monitors the fraction defective.
Asking questions about the current process in the hope that it will lead to important insights about why the current process isn't working as well as it could is called: A. the "5W2H approach" B. using quality circles C. benchmarking D. PDCA cycle E. none of the above
A. the "5W2H approach"
Studies on a machine that molds plastic water pipe indicate that when it is injecting 1-inch diameter pipe, the process standard deviation is 0.05 inches. The one-inch pipe has a specification of 1-inch plus or minus 0.10 inch. What is the process capability index (Cpk) if the long-run process mean is 1 inch? A. 0.50 B. 0.67 C. 1.00 D. 2.00 E. none of the above
B. 0.67 Use the Cpk formula to assess this process' capability.
The specifications for a product are 6 mm ± 0.1 mm. The process is known to operate at a mean of 6.05 with a standard deviation of 0.01 mm. What is the Cpk for this process? A. 3.33 B. 1.67 C. 5.00 D. 2.50 E. none of the above
B. 1.67 Cpk is used here since the process mean isn't centered in the specification interval.
Management behaviors supporting an organizational culture that encourages continuous improvement include which of the following? (I) develop a vision statement for the organization (II) develop a reward system that promotes the philosophy (III) institute continuous training programs (IV) make decisions that adhere to the philosophy A. I, II, and IV B. I, II, III, and IV C. I and III D. II, III, and IV E. II and IV
B. I, II, III, and IV
The Deming Prize was established by the ___. A. American Statistical Association B. Japanese C. North American Free Trade Association D. American Quality Society E. World Trade Organization
B. Japanese
A process results in a few defects occurring in each unit of output. Long-run, these defects should be monitored with ___________. A. p-charts B. c-charts C. x-bar charts D. r-charts E. o-charts
B. c-charts C-charts are used to monitor the number of defects per unit.
Focusing a supply chain on _________ is a modern way of ensuring high quality inputs and a ready supply of process-improvement ideas. A. lowest cost-per unit sourced B. close, collaborative ties with suppliers C. suppliers that emphasized continuous-flow production D. ISO 14000 customers E. partners pursuing similar strategies
B. close, collaborative ties with suppliers
Warranty service, processing of complaints, and costs of litigation are examples of ___. A. internal failure costs B. external failure costs C. appraisal costs D. prevention costs E. replacement costs
B. external failure costs
Cause-and-effect diagrams are sometimes called: A. Pareto diagrams B. fishbone (Ishikawa) diagrams C. run charts D. control charts E. none of the above
B. fishbone (Ishikawa) diagrams
The more effective and all-encompassing a firm's quality control and continuous improvement efforts, the less that company will need to rely on: A. insourcing. B. inspection. C. outsourcing. D. acceptance sampling. E. capability assessment.
B. inspection.
The four dimensions of quality that are sometimes used to determine fitness for use of a product are ___. A. performance, special features, durability, and service after sale B. performance, special features, conformance, and reliability C. special features, conformance, reliability, and durability D. performance, conformance, reliability, and durability E. special features, conformance, durability, and service after sale
B. performance, special features, conformance, and reliability
The basis for a statistical process control chart is a(the) __________. A. process capability B. sampling distribution C. control limit D. sample range E. sample mean
B. sampling distribution Control charts reflect the sampling distribution of an in control process.
A shift in the process mean for a measured characteristic would most likely be detected by a: A. p-chart B. x-bar chart C. c-chart D. R-chart E. s-chart
B. x-bar chart X-bar charts monitor the process mean.
The specification limit for a product is 8 cm and 10 cm. A process that produces the product has a mean of 9.5 cm and a standard deviation of 0.2 cm. What is the process capability, Cpk? A. 3.33 B. 1.67 C. 0.83 D. 2.50 E. none of the above
C. 0.83 Cpk is used here since the process mean isn't centered in the specification interval.
A time-ordered plot of sample statistics is called a(n) ______ chart. A. Statistical B. Inspection C. Control D. SIMO E. Limit
C. Control A control chart is a time-ordered plot of sample statistics.
A time-ordered plot of representative sample statistics is called a: A. Gantt chart B. SIMO-chart C. Control Chart D. Up-Down Matrix E. Standard deviation table
C. Control Chart Control charts are time-ordered plots of sample statistics.
Which isn't a cost of quality? A. Prevention cost B. External failure C. Extended Service Contracts D. Internal failure E. Appraisal costs
C. Extended Service Contracts
If a process is performing as it should, it is still possible to obtain observations which are outside of which limits? (I) tolerances (II) control limits (III) process variability A. I B. II C. I and II D. II and III E. I, II, and III
C. I and II Even capable, in control processes can have observations outside of control limits or tolerances.
A plot below the lower control limit on the range chart: (I) should be ignored since lower variation is desirable (II) may be an indication that process variation has decreased (III) should be investigated for assignable cause A. I and II B. I and III C. II and III D. II only E. I, II, and III
C. II and III Plots outside of control limits should be investigated.
The quality control improvement tool which distinguishes between the "important few" and the "trivial many" is ___. A. brainstorming. B. check sheets. C. Pareto analysis. D. cause-and-effect diagrams. E. fail-safe methods.
C. Pareto analysis.
Loss of business, liability, productivity and costs are consequences of ___. A. Labor Unions B. Globalization C. Poor Quality D. Robotics E. Micro-factories
C. Poor Quality
A quality improvement technique that involves the sharing of thoughts and ideas in a way that encourages unrestrained collective thinking is: A. Pareto analysis B. benchmarking C. brainstorming D. a control chart E. a check sheet
C. brainstorming
Which of the following relationships must always be incorrect? A. Tolerances > process variability > control limits B. Process variability > tolerances > control limits C. Tolerances > control limits > process variability D. Process variability > control limits > tolerances E. Process variability <Tolerances<control limits
C. Tolerances > control limits > process variability Process variability will always be greater than control limits.
The tool that is useful in the collection and organization of data is: A. a control chart B. a Pareto chart C. a check sheet D. a flow chart E. none of the above
C. a check sheet
Costs of inspectors, testing, test equipment, and labs are examples of ___. A. internal failure costs B. external failure costs C. appraisal costs D. prevention costs E. replacement costs
C. appraisal costs
The process of identifying other organizations that are best at some facet of your operations, and then modeling your organization after them is known as: A. continuous improvement B. employee empowerment C. competitive benchmarking D. copycatting E. industrial espionage
C. competitive benchmarking
Fixing a problem will often cost money; to minimize these costs it is best to find and fix the problem ___. A. just before shipping our product to the customer B. immediately after we complete the last operation C. during the design phase D. just before we begin the first production operation E. regardless of when you fix the problem, costs are about the same
C. during the design phase
Which of the following is not a step in the quality control process? A. define what is to be controlled B. compare measurements to a standard C. eliminate each of the defects as they are identified D. take corrective action if necessary E. evaluate corrective action
C. eliminate each of the defects as they are identified Eliminating defects is not part of quality control.
A point which is outside of the lower control limit on an R-chart: A. is an indication that no cause of variation is present B. should be ignored because it signifies better than average quality C. should be investigated because an assignable cause of variation might be present D. should be ignored unless another point is outside that limit E. is impossible since the lower limit is always zero
C. should be investigated because an assignable cause of variation might be present Points outside of the control limits should be investigated as signals of non-random variation being present.
A p-chart would be used to monitor _______. A. average shrinkage B. dispersion in sample data C. the fraction defective D. the number of defects per unit E. the range of values
C. the fraction defective The p-chart monitors the fraction defective.
A control chart used to monitor the process mean is the: A. p-chart B. R-chart C. x-bar chart D. c-chart E. Gantt chart
C. x-bar chart The x-bar chart monitors the process mean.
When a process is in control, it results in there being, on average, 16 defects per unit of output. C-chart limits of 4 and 28 would lead to a _______ chance of a Type I error. A. 67% B. 92% C. 33% D. 0.3% E. 5%
D. 0.3% These would be three-sigma limits.
Studies on a bottle-filling machine indicates it fills bottles to a mean of 16 ounces with a standard deviation of 0.10 ounces. What is the process specification, assuming the Cpk index of 1? A. 0.10 ounces B. 0.20 ounces C. 0.30 ounces D. 16.0 ounces plus or minus 0.30 ounces E. none of the above
D. 16.0 ounces plus or minus 0.30 ounces Use the Cpk formula to solve for the specification interval.
The probability of concluding that assignable variation exists when only random variation is present is: (I) the probability of a Type I error (II) known as the alpha risk (III) highly unlikely (IV) the sum of probabilities in the two tails of the normal distribution A. I and II B. I and IV C. II and III D. I, II, and IV E. I, III, and IV
D. I, II, and IV Incorrect signals can be on either side of the distribution.
Focusing attention on the most important problem areas is referred to as: A. quality circles B. quality assurance C. brainstorming D. Pareto analysis E. cause-and-effect analysis
D. Pareto analysis
A tool that is not used for quality is ___. A. Flowchart B. Histogram C. Parato Analysis D. Redesign E. Check sheets
D. Redesign
Deciding how much to invest in the prevention of defects can be analyzed using ___. A. EVPI B. Net Present Value C. Weighted Factor Analysis D. Return on Quality E. Breakeven Analysis
D. Return on Quality
TQM stands for: A. Taguchie Quality Methods B. Tactical Quality Measurements C. The Quality Matrix D. Total Quality Management E. Total Quantity Measurement
D. Total Quality Management
A quality circle is ___. A. responsible for quality B. total quality control C. an inspection stamp found on meat D. a voluntary group of employees E. none of the above
D. a voluntary group of employees
The purpose of the Malcolm Baldrige National Quality Award is to ___. A. stimulate efforts to improve quality B. recognize quality achievements of U.S. companies C. publicize successful quality programs D. all of the above E. distribute the grant money available for improved quality
D. all of the above
A control chart used to monitor the number of defects per unit is the: A. p-chart B. R-chart C. x-bar chart D. c-chart E. Gantt chart
D. c-chart C-charts monitor the number of defects per unit.
The quality control improvement tool that resembles a "fishbone" is ___. A. brainstorming B. check sheets C. Pareto analysis D. cause-and-effect diagrams E. fail-safe methods
D. cause-and-effect diagrams
The purpose of control charts is to: A. estimate the proportion of output that is acceptable B. weed out defective items C. determine if the output is within tolerances/specifications D. distinguish between random variation and assignable variation in the process E. provide meaningful work for quality inspectors
D. distinguish between random variation and assignable variation in the process Control charts are used to signal assignable variation.
Giving workers responsibility for quality improvements and authority to make changes is known as: A. continuous improvement B. passing the buck C. benchmarking D. employee empowerment E. employee involvement
D. employee empowerment
Which of the following is not a goal of process improvement? A. increasing customer satisfaction B. reducing waste C. achieving higher quality D. identifying the cause of a problem E. All are the goals.
D. identifying the cause of a problem
Quality planning and administration, quality training, and quality control procedures are examples of ___. A. internal failure costs B. external failure costs C. appraisal costs D. prevention costs E. replacement costs
D. prevention costs
The typical difference between "quality circles" and "continuous improvement teams" is ______. A. Quality circles work on product design only. B. Continuous improvement teams work on product and process design. C. Continuous improvement teams use only engineers while quality circles use just the workers doing the work. D. the amount of employee empowerment E. There is no difference-they are just the same.
D. the amount of employee empowerment
The optimum level of inspection is where the: A. cost of inspection is minimum B. cost of passing defectives is minimum C. total cost of inspection and defectives is maximum D. total cost of inspection and defectives is minimum E. difference between inspection and defectives costs is minimum
D. total cost of inspection and defectives is minimum At the optimum level these costs are, in total, minimized.
ISO 9000 standards do not have a requirement for ___. A. resource B. remedial C. systems D. training E. management
D. training
Organizations should work to improve process capability so that quality control efforts can become more ________. A. effective B. efficient C. necessary D. unnecessary E. widespread
D. unnecessary Increasing process capability reduces the necessity for quality control.
The range chart (R-chart) is most likely to detect a change in: A. proportion B. mean C. number defective D. variability E. sample size
D. variability The range chart monitors variability.
When a process is in control, it results in there being, on average, 16 defects per unit of output. C-chart limits of 8 and 24 would lead to a _______ chance of a Type I error. A. 67% B. 92% C. 33% D. .03% E. 5%
E. 5% These would be two-sigma limits
The quality certification that deals primarily with conformance to customer requirements is ISO __________; ISO __________ is concerned primarily with the organization's effect on the environment. A. 14000; 24700 B. 9000; 24700 C. 24700; 9000 D. 14000; 9000 E. 9000; 14000
E. 9000; 14000
ISO 9000 currently requires _____ of a certified organization. A. Quarterly reporting B. Product diversity C. Annual audits D. A minimum of four supervisory levels E. Continuous improvement
E. Continuous improvement
Managers have obligations to a wide variety of stakeholders such as shareholders, employees and customers. When considering outsourcing production to offshore suppliers, managers have to weigh _____. I) Cost benefits that might make shareholders wealthier II) Quality issues that might make firms less productive and/or products riskier III) The investments already tied up in relationships with existing suppliers A. I B. II C. III D. I and II only E. I, II and III
E. I, II and III
The process capability index (Cpk) may mislead if: (I) the process is not stable. (II) the process output is not normally distributed. (III) the process is not centered. A. I and II B. I and III C. II and III D. II only E. I, II and III
E. I, II and III When using Cpk these concerns should be addressed.
A c-chart is used for: A. means B. ranges C. percent defective D. fraction defective per unit E. number of defects per unit
E. number of defects per unit C-charts monitor the number of defects per unit.
Which of the following is an element of TQM? A. continual improvement B. competitive benchmarking C. operations Manager empowerment D. team approach E. all of the above
E. all of the above
Inspection is a(n): A. prevention. B. control. C. monitoring. D. corrective. E. appraisal.
E. appraisal.
The "5W2H approach" involves: A. measuring width and height B. using 7 people C. using 2 people D. using 9 people E. asking questions
E. asking questions
Quality control, in contrast to quality assurance, is implemented: A. after production. B. before inspection. C. by self-directed teams. D. by top management. E. during production.
E. during production.
Before a dimension of quality can be made operationally useful, it must be restated in some ___________ form. A. certifiable B. manipulative C. marketable D. qualitative E. measurable
E. measurable
Which of the following quality control sample statistics indicates a quality characteristic that is an attribute? A. mean B. variance C. standard deviation D. range E. proportion
E. proportion Proportions would be control with attribute control charts.
Quality certification refers to a process of 100 percent inspection to catch all defective products before they leave the company; this allows every item to certified defect free.
FALSE
Quality of design refers to the degree to which goods and services achieve the intent of the designers.
FALSE
Regardless of superior quality, consumers won't pay premium prices.
FALSE
So long as quality input resources are used to make a product, we can expect quality output from the process.
FALSE
Suppliers are not included in quality assurance and quality improvement efforts in TQM; they should worry about their own problems.
FALSE
The Baldrige award can only be won by manufacturing organizations.
FALSE
The PDSA cycles is also referred to as the Baldrige Wheel.
FALSE
The benchmark organization must be chosen from the same industry in order for its methods to be applicable.
FALSE
The causes of variation in any process can be identified through the general categories of people, procedures, education and age.
FALSE
The seven dimensions of quality are important for products but are not applicable in service organizations.
FALSE
The term "quality at the source" refers primarily to the practice of requiring each of our vendors to provide quality parts and materials.
FALSE
Total quality management is a collection of techniques, such as quality control charts, ISO 9000, and quality function deployment.
FALSE
When problems arise in a total quality managed organization, it is important to assign blame and punish the worker responsible for causing the problem.
FALSE
Zero defects requires 100% inspection of the final product.
FALSE
A c-chart is used to monitor the total number of defectives in the output of a process.
FALSE A c-chart is used to monitor the number of defects per unit, not defective units.
Approving the effort that occurs during the production process is known as acceptance sampling.
FALSE Acceptance sampling occurs before or after the production process.
A process that exhibits random variability would be judged to be out of control.
FALSE All processes exhibit random variability.
Approximately 99.7% of sample means will fall within ± two standard deviations of the process mean if the process is under control.
FALSE Approximately 99.7% of sample means will fall within ± three standard deviations of the process mean.
Attributes need to be measured, variable data can be counted.
FALSE Attributes need to be counted, variable data is measured.
Control limits are based on multiples of the process standard deviation.
FALSE Control limits are based on multiples of the standard deviation of the sample statistic.
Control limits used on process control charts are specifications established by design or customers.
FALSE Control limits are independent of specifications.
The process capability index (indicated by Cpk) can be used only when the process is centered.
FALSE Cpk can be used whether or not the process is centered.
The greater the capability ratio, the higher the rejects.
FALSE Greater capability reduces rejects.
The larger the process variation, the tighter the specifications should be.
FALSE Greater variation would lead to wider specifications.
Non-random variation is likely whenever all observations are between the LCL and UCL.
FALSE If all observations are between the LCL and UCL, then the process would be considered in control.
Even if the process is not centered, the process capability index (indicated by Cpk) is very useful.
FALSE If the process is not centered, Cpk is not useful.
An R value of zero (on a range chart) means that the process must be in control since all sample values are equal.
FALSE If the sample size is sufficiently large, an R of zero could indicate an out of control process.
Processes that are in control eliminate variations.
FALSE In control, processes are free of non-random variation.
Range charts and p-charts are both used for variable data.
FALSE P-charts are used with attribute data.
Range charts are used mainly with attribute data.
FALSE Range charts are used with variable data.
Range control charts are used to monitor process central tendency.
FALSE Ranger charts monitor variability.
Run tests give managers an alternative to control charts; they are quicker and cost less.
FALSE Runs tests are not alternatives to control charts.
Statistical Process Control is the measurement of rejects in the final product.
FALSE SPC is the evaluation of the process.
Statistical process control focuses on the acceptability of process output.
FALSE Statistical process control focuses on the variability of processes.
The Taguchi Cost Function suggests that the capability ratio can be improved by extending the spread between LCL and UCL.
FALSE The Taguchi cost function suggests that reducing variation is key.
The best way to assure quality is to use extensive inspection and control charts.
FALSE The best way to assure quality is to make sure processes are highly capable.
The number of defective parts in a sample is an example of variable data because it will "vary" from one sample to another.
FALSE The number of defective parts in a sample is an example of attribute data.
The optimum level of inspection occurs when we catch at least 98.6 percent of the defects.
FALSE The optimum level of inspection is when the sum of inspection costs and the cost of passing defectives are equal.
Tolerances represent the control limits we use on the charts.
FALSE Tolerances are specification limits, not control limits.
Statistical Process Control is the measurement of rejects in the final product.
FALSE SPC is the evaluation of the process.
The optimum level of inspection occurs when we catch at least 98.6 percent of the defects.
FALSE The optimum level of inspection is when the sum of inspection costs and the cost of passing defectives are equal.
Concluding a process is out of control when it is not is known as a Type I error.
TRUE A Type I error involves erroneously concluding that a process is out of control.
A c-chart is used to monitor the number of defects per unit for process output.
TRUE A c-chart monitors the number of defects per unit for process output.
If a point on a control chart falls outside one of the control limits, this suggests that the process output is non-random and should be investigated.
TRUE A point outside the control limits suggests non-random variation.
The output of a process may not conform to specifications even though the process may be statistically "in control."
TRUE A process can be free of non-random variation and still not meet specifications.
"Assignable variation" is variation due to a specific cause, such as tool wear.
TRUE Assignable variation is specific cause variation.
Quality control is assuring that processes are performing in an acceptable manner.
TRUE Control is used to monitor the performance of processes.
When a process is not centered, its capability is measured in a slightly different way. The symbol for this case is Cpk.
TRUE Cpk is used when the process is not centered.
Patterns of data on a control chart suggest that the process may have non-random variation.
TRUE Ideally, the data on a control chart will have no pattern.
A p-chart is used to monitor the fraction of defectives in the output of a process.
TRUE P-charts involve the fraction of defectives.
"Process capability" compares "process variability" to the "tolerances."
TRUE Process variability influences how much output falls outside of tolerances.
Control limits tend to be wider for more variable processes.
TRUE Process with inherently more variability will naturally have wider control limits.
Run tests are useful in helping to identify nonrandom variations in a process.
TRUE Runs tests are useful to identify non-randomness in patterns.
A run test checks a sequence of observations for randomness.
TRUE Runs tests can be used to detect nonrandomness in sequences of observations.
A lower control limit must by definition be a value less than an upper control limit.
TRUE The lower limit must be smaller than the upper limit.
The variation of a sampling distribution is tighter than the variation of the underlying process distribution.
TRUE The sampling distribution exhibits less variation than the underlying process.
High-cost, low-volume items often require careful inspection since we make them so infrequently.
TRUE These are good candidates for inspection.
The amount of inspection we choose can range from no inspection at all to inspecting each item numerous times.
TRUE These are the extremes of inspection.
Attribute data are counted, variable data are measured.
TRUE These distinguish attribute from variable data.
The optimum level of inspection minimizes the sum of inspection costs and the cost of passing defectives.
TRUE This represents the optimum balance between inspection and failure costs.
Variation in a sample statistic collected from a process may be either random variation or assignable variation - or both.
TRUE Total variation can consist of both random and assignable variation.