Chap 006

Chapter 06 - Quality Management and Six Sigma

Chapter 06Quality Management and Six Sigma

Learning Objectives for Chapter 6

1. Understand total quality management.2. Discuss how quality is measured and be aware of the different

dimensions of quality.3. Explain the define, measure, analyze, improve, and control (DMAIC)

quality improvement process.4. Show how to calculate the capability of a process.5. Describe how processes are monitored with control charts.6. Understand acceptance sampling concepts.

True / False Questions

1. TQM was defined in the textbook as managing the entire organization so that it excels on all dimensions of products and services that are important to the customer. True False

2. One SPC tool used in total quality management is the run chart. True False

3. An operational goal of total quality management is the careful design of the product or service. True False

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4. An operational goal of total quality management is ensuring that the organization's systems can consistently produce the product or service as it is designed. True False

5. Design quality refers to the inherent value of the product in the marketplace. True False

6. One of the tools of a quality control department that is used in a TQM program is acceptance sampling. True False

7. One of the tools of a quality control department that is used in a TQM program is leadership. True False

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8. In 1997 the Malcolm Baldrige National Quality Improvement Act established the U.S.'s annual award for total quality management. True False

9. Conformance quality is a strategic decision for the firm. True False

10. The Malcolm Baldrige National Quality Award represents the U. S. government's endorsement of quality as an essential part of successful business strategy. True False

11. While business organizations can seek to achieve the Baldrige National Quality Award, educational institutions, like universities, can't. True False

12. While small business organizations can seek to achieve the Baldrige National Quality Award, health care organizations, like hospitals, can't. True False

13. A quality guru named Philip Crosby defined quality as fitness for use. True False

14. A quality guru named Philip Crosby defined quality as conformance to requirements. True False

15. A quality guru named Joseph M. Juran defined quality as fitness for use. True False

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16. A quality guru named Philip Crosby suggested a general approach to quality management should involve prevention, not inspection. True False

17. A quality guru named Philip Crosby is well known for his "14 points" of quality. True False

18. Fundamental to any quality program is the determination of quality specifications and the costs of achieving (or not achieving) those specifications. True False

19. The term "conformance quality" refers to the relative level of performance of a product as compared to competing products. For instance, certain luxury sedans are said to be of "higher quality" than some low-priced sub-compact automobiles. True False

20. "Quality at the source" refers to the degree to which product or service design specifications are met. True False

21. Design quality in products refers to the degree to which product design specifications are met. True False

22. One of the definitions for the cost of quality is that it represents the costs attributable to the production of quality that is not 100 percent perfect. True False

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23. Continuous improvement is a management philosophy that approaches the challenge of product and process improvement as a never-ending process of achieving small wins. True False

24. Six-sigma refers to the philosophy and methods that some leading companies use to eliminate defects in their products and processes. True False

25. A process that is in six-sigma control will produce no more than two defects out of every million units. True False

26. A DMPO is essentially the same thing as a DMAIC. True False

27. An opportunity flow diagram is used to separate the value-added from the non-value-added steps in a process. True False

28. An opportunity flow diagram is a time sequenced chart showing plotted values measuring the flow of end product or components. True False

29. Variation in production systems that is caused by factors that can be clearly identified and possibly even managed is called assignable variation. True False

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30. An example of assignable variation in a production system may be that workers are not identically trained. True False

31. An example of assignable variation in a production system may be that a machine is not adjusted properly. True False

32. Variation that is inherent in a production process itself is called assignable variation. True False

33. Variation that is inherent in a production process itself is called common variation. True False

34. It is impossible to have zero variability in production processes. True False

35. Genichi Taguchi's view of the cost of quality is that variance is a discontinuous function. True False

36. The capability index is used to gauge economic changes in service systems. True False

37. Process control is concerned with monitoring quality after the product or service has been produced. True False

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38. Statistical process control involves testing random samples of output from a process to determine whether the process is producing items within a pre-selected range. True False

39. Measurement by attributes means taking a sample, measuring the attribute in question and determining the level of quality in the population from which the sample was drawn. True False

40. Attributes are those quality characteristics that are classified as either conforming or not conforming to specifications. True False

41. A quality control chart has upper and lower control limits expressed as lines on a chart. As long as the sample values fall between these two lines there is no need to investigate process behavior. True False

42. The "p" chart is only useful for sampling that deals with continuous variables. True False

43. The value for "z" used in quality control charts is based on the degree of confidence you want to have in the resulting UCL and LCL values. True False

44. If the fraction defective is 0.12 based on a sample size of 16, the standard deviation used in the "p" chart is about 0.08. True False

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45. If the fraction defective is 0.4 based on a sample size of 100, the standard deviation used in the "p" chart is about 0.10. True False

46. To obtain a 99.7 percent confidence level in a "p" chart we would use a value of 3 for "z". True False

47. Acceptance sampling is performed on goods that already exist to determine what percentage of items conforms to specifications. True False

48. In acceptance sampling, the number of units in the sample (n) is determined by the interaction of the acceptable quality level (AQL), the lot tolerance percent defective (LTPD), the probability of rejecting a high quality lot (alpha) and the probability of accepting a low quality lot (beta). True False

49. In acceptance sampling, the value for the acceptance number (c) is determined by the interaction of the acceptable quality level (AQL), the lot tolerance percent defective (LTPD), the probability of rejecting a high quality lot (alpha) and the probability of accepting a low quality lot (beta). True False

50. AQL stands for accepting questionable lots in production quality management. True False

51. LTPD in acceptance sampling stands for "lots of tolerance for parts defective." True False

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52. The Greek letter alpha is associated with consumer's risk. True False

53. The probability associated with rejecting a high quality lot is denoted in acceptance sampling with the Greek letter alpha. True False

54. The probability associated with accepting a low quality lot is denoted in acceptance sampling with the Greek letter alpha. True False

55. The producer's risk associated with rejecting a high quality lot is denoted in acceptance sampling with the Greek letter beta. True False

56. Total, one-hundred percent, inspection can never be cost justified. True False

57. One-hundred percent inspection is justified when the cost of inspection is not very much. True False

58. Sampling plans are generally displayed graphically through the use of operating characteristic (OC) curves. True False

59. The capability index (Cpk) calculates the percentage of items being produced within specifications. True False

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60. The capability index (Cpk) indicates the position of the mean and tails of a processes variance relative to design specifications. True False

61. Standard practice in statistical process control for variables is to set control limits so that 95 percent of the sample means will fall within the UCL and the LCL. True False

62. In variables sampling the actual measurements of the variable observed are used regardless of whether the unit is good or bad. True False

Multiple Choice Questions

63. The philosophical leaders of the quality movement, Philip Crosby, W. Edwards Deming, and Joseph M. Juran had the same general message about what it took to achieve outstanding quality. Which of the following was not part of that message? A. Quality is freeB. Leadership from senior managementC. Customer focusD. Total involvement of the workforceE. Continuous improvement

64. The philosophical leaders of the quality movement, Philip Crosby, W. Edwards Deming, and Joseph M. Juran had the same general message about what it took to achieve outstanding quality. Which of the following was part of that message? A. Fourteen steps for quality managementB. Quality is freeC. Customer focusD. Zero defectsE. Six-sigma

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65. An analytical tool used in six-sigma quality improvement programs is which of the following? A. LeadershipB. Continuous improvementC. Quick responseD. Partnership developmentE. Checksheets

66. Which of the following is not an analytical tool used in six-sigma quality improvement programs? A. Run chartsB. Pass chartsC. Cause-and-effect diagramsD. FlowchartsE. Pareto charts

67. A flow chart as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control

68. A fishbone diagram as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control

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69. An opportunity flow diagram as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control

70. A Pareto chart as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control

71. Which of the following is an analytical tool used in six-sigma quality improvement programs? A. LeadershipB. Pareto ChartsC. Management by factD. Continuous improvementE. Kaizen

72. Which of the following is not an analytical tool used in six-sigma quality improvement programs? A. FlowchartsB. Run chartsC. Control chartsD. Pareto analysisE. Tendency analysis

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73. Failure mode and effect analysis is used in six-sigma projects. It involves which of the following? A. Closely examining each rejected part to determine the causeB. A careful sampling planC. Calculating a risk priority number for each possible failureD. Reporting the effect each failure has had on a customerE. Multivariate testing

74. Design of experiments is a statistical methodology often used in six-sigma projects. It aims to accomplish which of the following? A. Keep careful track of the occurrences of each possible defectB. Determine the cause and effect relationships between process variables and outputC. Report defects to management on a Pareto chartD. Carefully change each individual process variable until the cause of a defect is foundE. Eliminate defects by finding out who or what is causing them

75. The Malcolm Baldrige award selection process helps improve quality and productivity by which of the following means? A. Stimulating foreign based suppliers of American companies to improve qualityB. Reporting quality levels among American firmsC. Identifying American firms with the most difficult quality problemsD. Providing feedback to applicants by the examinersE. Helping Baldrige award winners increase their sales

76. Which of the following are eligible companies to be considered for the Baldrige award? A. Auditing firmsB. Offshore suppliers to U. S. companiesC. Firms operating only outside the U. S.D. State Government agenciesE. None of the above

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77. Which of the following are not eligible to be considered for the Baldrige Award? A. Small businessesB. Health care organizationsC. Educational institutionsD. State highway patrol organizationsE. Nuclear power plants

78. The primary purpose of the Malcolm Baldrige National Quality Award is which of the following? A. To encourage the spread of statistical quality controlB. To improve human resource development and management in manufacturingC. To improve competitiveness of American firmsD. To prove that American firms were competitive in qualityE. To emphasize the use of quantitative methods in process management

79. The Grading Criteria of the Baldrige Award for total quality management includes which of the following? A. Future plansB. Information and analysisC. StandardizationD. ControlE. None of the above

80. The Malcolm Baldrige National Quality Award is given to organizations that have done which of the following? A. Instituted a six-sigma approach to total quality controlB. Demonstrated a high level of product qualityC. Demonstrated outstanding quality in their products and processesD. Have a world-class quality control functionE. Most significantly improved their product quality levels

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81. Which of the following is not a category reported in applying for the Baldrige Award? A. Corporate leadershipB. Use of statistical quality control toolsC. Business resultsD. Consumer and market focusE. Strategic planning

82. The dimension of design quality that concerns the sensory characteristics of the product is which of the following? A. FeaturesB. ServiceabilityC. Perceived qualityD. ReputationE. Aesthetics

83. The dimension of design quality that concerns the consistency of performance over time or the probability of failing is which of the following? A. ResponseB. ServiceabilityC. ReliabilityD. ReputationE. Perceived quality

84. The dimension of design quality that concerns secondary characteristics is which of the following? A. FeaturesB. ServiceabilityC. ReliabilityD. ReputationE. Perceived quality

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85. Which of the following is a dimension of design quality? A. PriceB. FeaturesC. ColorD. WeightE. Quality at the source

86. Which of the following is a dimension of design quality? A. AestheticsB. PriceC. Quality at the sourceD. DistributionE. Leadership

87. Which of the following is a basic assumptions that justify an analysis of the costs of quality? A. Failures are causedB. Prevention is more expensiveC. Performance can be learnedD. Rules of thumb don't always workE. Appraisal costs are less than prevention costs

88. A cost of quality classification is which of the following? A. Material costsB. Prevention costsC. Variable overheadD. Direct laborE. Inventory costs

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89. Which of the following is the cost of quality classification for costs such as scrap, rework, or repair? A. Appraisal costsB. Prevention costsC. External failure costsD. Internal failure costsE. Rework and wastage

90. Which of the following is the cost of quality classification for costs such as inspection, testing, and other tasks to ensure that the product or process is acceptable? A. Appraisal costsB. Prevention costsC. External failure costsD. Internal failure costsE. Checking costs

91. Which of the following is the cost of quality classification for costs such as defects that pass through the system, such as customer warranty replacements, loss of customer or goodwill, handling complaints, and product repair? A. Appraisal costsB. Prevention costsC. External failure costsD. Customer return costE. Workmanship costs

92. Which of the following tools uses a graphical representation of the production process to suggest potential sources of process variation? A. Process flow diagramB. Check sheetC. Pareto chartD. HistogramE. Run chart

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93. In monitoring process quality we might use which of the following statistics? A. Absolute valuesB. Percentage deviation from tolerance centersC. "k" values for the sample meanD. Logarithmic control intervalsE. Difference between the highest and lowest value in a sample

94. You have just used the capability index (Cpk) formulas to compute the two values "min [2, 2.5]." Which of the following is the proper interpretation of these numbers? A. The true capability index value is 2.5B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. The true capability index value is between 2 and 2.5

95. You have just used the capability index (Cpk) formulas to compute the two values "min [1, 1]." Which of the following is the proper interpretation of these numbers? A. The true capability index value is exactly 1B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. None of the above

96. You have just used the capability index (Cpk) formulas to compute the two values "min [1.5, 1]." Which of the following is the interpretation of these numbers? A. The true capability index value is 1B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. The true capability index value is between 1.5 and 1

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97. Quality control charts usually have a central line and upper and lower control limit lines. Which of the following is not a reason that the process being monitored with the chart should be investigated? A. A large number of plots are close to the upper or lower control linesB. Erratic behavior of the plotsC. A single plot falls above or below the control limitsD. A change in raw materials or operatorsE. A run of five above the central line

98. Quality control charts usually have a central line and upper and lower control limit lines. Which of the following is a reason that the process being monitored with the chart should be investigated? A. A single plot falls above or below the control limitsB. Normal behaviorC. A large number of plots are on or near the central lineD. No real trend in any directionE. A change in raw materials or operators

99. If there are 120 total defects from 10 samples, each sample consisting of 10 individual items in a production process, which of the following is the fraction defective that can be used in a "p" chart for quality control purposes? A. 120B. 10C. 8D. 1.2E. 0.8

100. If there are 400 total defects from 8 samples, each sample consisting of 20 individual items in a production process, which of the following is the fraction defective that can be used in a "p" chart for quality control purposes? A. 400B. 160C. 2.5D. 1.0E. 0.4

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101. You want to determine the upper control line for a "p" chart for quality control purposes. You take several samples of a size of 100 items in your production process. From the samples you determine the fraction defective is 0.05 and the standard deviation is 0.01. If the desired confidence level is 99.7 percent, which of the following is the resulting UCL value for the line? A. 0.39B. 0.08C. 0.06D. 0.05E. None of the above

102. You want to determine the lower control line for a "p" chart for quality control purposes. You take several samples of a size of 50 items in your production process. From the samples you determine the fraction defective is 0.006 and the standard deviation is 0.001. If the desired confidence level is 99.7 percent, which of the following is the resulting LCL value for the line? A. 0.0B. 0.002C. 0.003D. 0.004E. None of the above

103. You want to determine the control lines for a "p" chart for quality control purposes. If the desired confidence level is 99 percent, which of the following values for "z" would you use in computing the UCL and LCL? A. 0.99B. 2C. 2.58D. 3E. None of the above

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104. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 2,500, the number of samples is 100, and the sample size is 50, which of the following would be the standard deviation used in developing the control lines? A. 0.4900B. 0.2499C. 0.1556D. 0.0707E. 0.02499

105. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 560, the number of samples is 70, and the sample size is 80, which of the following would be the standard deviation used in developing the control lines? A. 0.9000B. 0.4556C. 0.0335D. 0.0011E. 0.0112

106. For which of the following should we use a "p" chart to monitor process quality? A. Defective electrical switchesB. Errors in the length of a pencilC. Weight errors in cans of soupD. Temperature of entrees in a restaurantE. Letter grades on a final examination

107. For which of the following should we use a "p" chart to monitor process quality? A. The dimensions of brick entering a kilnB. Lengths of boards cut in a millC. The weight of fluid in a containerD. Grades in a freshman "pass/fail" courseE. Temperatures in a classroom

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108. With which of the following should we use an "X-bar" chart based on sample means to monitor process quality? A. Grades in a freshman "pass/fail" courseB. Tire pressures in an auto assembly plantC. Vehicles passing emissions inspectionD. Computer software errorsE. Number of units with missing operations

109. Which of the following should we use an "R" chart to monitor process quality? A. Grades in a freshman "pass/fail" courseB. Tire pressures in an auto assembly plantC. Vehicles passing emissions inspectionD. Computer software errorsE. Number of units with missing operations

110. Which of the following should we use an "R" chart to monitor process quality? A. Weighing trucks at a highway inspection station to determine if they are overloadedB. Deciding whether an airliner has sufficient fuel for its tripC. Student grades measured from 1 to 100D. Determining whether vehicles from a motor pool will runE. Determining the accuracy of a forecast of "snow"

111. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99.7 percent, and the average of the sample means is 24. Which of the following is your UCL? A. 36B. 24C. 12D. 4E. None of the above

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112. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99 percent, and the average of the sample means is 20. Which of the following is your LCL? A. 36B. 24C. 9.68D. 16.79E. 30.32

113. You want to develop a three-sigma "R" chart. You know the average range is 5 based on several samples of size 10. Which of the following is the resulting UCL? A. 20.9B. 8.9C. 7.02D. 5E. 3.1

114. You want to develop a three-sigma "R" chart. You know the average range is 12 based on several samples of size 6. Which of the following is the resulting LCL? A. 20.0B. 18.3C. 7.02D. 5.6E. 0.0

115. If you are going to develop an "X-bar" chart based on range statistics and you are using a sample size of 12 for your charting purposes. Which of the following is the A2 factor for the "X-bar" chart? A. 0.37B. 0.31C. 0.27D. 0.22E. .18

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116. If you are going to develop an "R" chart based on range statistics and you are using a sample size of 9 for your charting purposes. Which of the following is the lower control limit D3 factor for the chart? A. 0.08B. 0.14C. 0.18D. 0.22E. 0.29

117. If you are going to develop an "R" chart based on range statistics and you are using a sample size of 15 for your charting purposes. Which of the following is the upper control limit D4 factor for the chart? A. 1.65B. 1.70C. 1.76D. 1.87E. 1.92

Fill in the Blank Questions

118. The National Quality Award in the United States is named ______________________. ________________________________________

119. The expenditures related to achieving product or service quality including the costs of appraisal and prevention of defects are called ______________________. ________________________________________

120. ISO-9000 standards were developed to ______________________ ________________________________________

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121. Six-sigma programs believe that each step in a process is an opportunity to produce defects. These programs seek to reduce defects by working on processes to reduce ______________________. ________________________________________

122. If the fraction defective is 0.12 based on a sample size of 16, the standard deviation to be used when constructing a "p" chart is ______________________. ________________________________________

123. If the fraction defective is 0.4 based on a sample size of 100, the standard deviation used in constructing the "p" chart is ______________________. ________________________________________

124. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 2,000, the number of samples is 100, and the sample size is 50, the standard deviation used in developing the control lines would be ______________________. ________________________________________

125. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 560, the number of samples is 70, and the sample size is 80, the standard deviation used in developing the control lines would be ______________________. ________________________________________

126. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99.7 percent, and the average of the sample means is 24. The UCL is ______________________. ________________________________________

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127. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99 percent, and the average of the sample means is 20. The LCL is ______________________. ________________________________________

128. You want to develop a three-sigma "R" chart. You know the average range is 5 based on several samples of size 10. The resulting UCL is ______________________. ________________________________________

129. You want to develop a three-sigma "R" chart. You know the average range is 12 based on several samples of size 6. The resulting LCL is ____________________. ________________________________________

Short Answer Questions

130. The symbol designating the capability index is ______________________.


131. All else being equal, the magnitude of the effect of lot size on sample size is ______________________. ________________________________________

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132. You have 75 total defects from 100 different samples of 15. The value of "p" is ______________________. ________________________________________

133. Lots are defined as low quality when the percentage of defective units is greater than ______________________. ________________________________________

Essay Questions

134. What is the difference between the concepts of design quality and conformance quality?

135. What does it mean when we say that a process is capable?

136. Explain the difference between producer's risk and consumer's risk in acceptance sampling.

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137. What is the difference between statistical quality control and statistical process control?

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Chapter 06 Quality Management and Six Sigma Answer Key

True / False Questions

1. TQM was defined in the textbook as managing the entire organization so that it excels on all dimensions of products and services that are important to the customer. TRUE

AACSB: AnalyticDifficulty: EasyLearning Objective: 1Taxonomy: KnowledgeTopic: Total Quality Management

2. One SPC tool used in total quality management is the run chart. TRUE

AACSB: AnalyticDifficulty: EasyLearning Objective: 5Taxonomy: KnowledgeTopic: Process Control Procedures

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3. An operational goal of total quality management is the careful design of the product or service. TRUE


4. An operational goal of total quality management is ensuring that the organization's systems can consistently produce the product or service as it is designed. TRUE


5. Design quality refers to the inherent value of the product in the marketplace. TRUE

AACSB: AnalyticDifficulty: EasyLearning Objective: 2Taxonomy: KnowledgeTopic: Quality Specifications and Quality Costs

6. One of the tools of a quality control department that is used in a TQM program is acceptance sampling. TRUE


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7. One of the tools of a quality control department that is used in a TQM program is leadership. FALSE


8. In 1997 the Malcolm Baldrige National Quality Improvement Act established the U.S.'s annual award for total quality management. FALSE


9. Conformance quality is a strategic decision for the firm. FALSE

AACSB: AnalyticDifficulty: MediumLearning Objective: 1Taxonomy: KnowledgeTopic: Total Quality Management

10. The Malcolm Baldrige National Quality Award represents the U. S. government's endorsement of quality as an essential part of successful business strategy. TRUE


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11. While business organizations can seek to achieve the Baldrige National Quality Award, educational institutions, like universities, can't. FALSE


12. While small business organizations can seek to achieve the Baldrige National Quality Award, health care organizations, like hospitals, can't. FALSE


13. A quality guru named Philip Crosby defined quality as fitness for use. FALSE


14. A quality guru named Philip Crosby defined quality as conformance to requirements. TRUE


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15. A quality guru named Joseph M. Juran defined quality as fitness for use. TRUE


16. A quality guru named Philip Crosby suggested a general approach to quality management should involve prevention, not inspection. TRUE


17. A quality guru named Philip Crosby is well known for his "14 points" of quality. FALSE


18. Fundamental to any quality program is the determination of quality specifications and the costs of achieving (or not achieving) those specifications. TRUE


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19. The term "conformance quality" refers to the relative level of performance of a product as compared to competing products. For instance, certain luxury sedans are said to be of "higher quality" than some low-priced sub-compact automobiles. FALSE

AACSB: AnalyticDifficulty: MediumLearning Objective: 2Taxonomy: KnowledgeTopic: Quality Specifications and Quality Costs

20. "Quality at the source" refers to the degree to which product or service design specifications are met. FALSE


21. Design quality in products refers to the degree to which product design specifications are met. FALSE


22. One of the definitions for the cost of quality is that it represents the costs attributable to the production of quality that is not 100 percent perfect. TRUE


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23. Continuous improvement is a management philosophy that approaches the challenge of product and process improvement as a never-ending process of achieving small wins. TRUE


24. Six-sigma refers to the philosophy and methods that some leading companies use to eliminate defects in their products and processes. TRUE


25. A process that is in six-sigma control will produce no more than two defects out of every million units. FALSE


26. A DMPO is essentially the same thing as a DMAIC. FALSE

AACSB: AnalyticDifficulty: EasyLearning Objective: 3Taxonomy: KnowledgeTopic: Six-Sigma Quality

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27. An opportunity flow diagram is used to separate the value-added from the non-value-added steps in a process. TRUE


28. An opportunity flow diagram is a time sequenced chart showing plotted values measuring the flow of end product or components. FALSE


29. Variation in production systems that is caused by factors that can be clearly identified and possibly even managed is called assignable variation. TRUE


30. An example of assignable variation in a production system may be that workers are not identically trained. TRUE


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31. An example of assignable variation in a production system may be that a machine is not adjusted properly. TRUE


32. Variation that is inherent in a production process itself is called assignable variation. FALSE


33. Variation that is inherent in a production process itself is called common variation. TRUE


34. It is impossible to have zero variability in production processes. TRUE


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35. Genichi Taguchi's view of the cost of quality is that variance is a discontinuous function. FALSE


36. The capability index is used to gauge economic changes in service systems. FALSE

AACSB: AnalyticDifficulty: EasyLearning Objective: 4Taxonomy: KnowledgeTopic: Statistical Quality Control

37. Process control is concerned with monitoring quality after the product or service has been produced. FALSE


38. Statistical process control involves testing random samples of output from a process to determine whether the process is producing items within a pre-selected range. TRUE

AACSB: AnalyticDifficulty: EasyLearning Objective: 6Taxonomy: KnowledgeTopic: Acceptance Sampling

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39. Measurement by attributes means taking a sample, measuring the attribute in question and determining the level of quality in the population from which the sample was drawn. FALSE

AACSB: AnalyticDifficulty: MediumLearning Objective: 6Taxonomy: KnowledgeTopic: Acceptance Sampling

40. Attributes are those quality characteristics that are classified as either conforming or not conforming to specifications. TRUE


41. A quality control chart has upper and lower control limits expressed as lines on a chart. As long as the sample values fall between these two lines there is no need to investigate process behavior. FALSE

AACSB: AnalyticDifficulty: EasyLearning Objective: 5Taxonomy: AnalysisTopic: Process Control Procedures

42. The "p" chart is only useful for sampling that deals with continuous variables. FALSE


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43. The value for "z" used in quality control charts is based on the degree of confidence you want to have in the resulting UCL and LCL values. TRUE


44. If the fraction defective is 0.12 based on a sample size of 16, the standard deviation used in the "p" chart is about 0.08. TRUE

AACSB: AnalyticDifficulty: MediumLearning Objective: 6Taxonomy: AnalysisTopic: Acceptance Sampling

45. If the fraction defective is 0.4 based on a sample size of 100, the standard deviation used in the "p" chart is about 0.10. FALSE

AACSB: AnalyticDifficulty: EasyLearning Objective: 6Taxonomy: AnalysisTopic: Acceptance Sampling

46. To obtain a 99.7 percent confidence level in a "p" chart we would use a value of 3 for "z". FALSE


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47. Acceptance sampling is performed on goods that already exist to determine what percentage of items conforms to specifications. TRUE


48. In acceptance sampling, the number of units in the sample (n) is determined by the interaction of the acceptable quality level (AQL), the lot tolerance percent defective (LTPD), the probability of rejecting a high quality lot (alpha) and the probability of accepting a low quality lot (beta). TRUE


49. In acceptance sampling, the value for the acceptance number (c) is determined by the interaction of the acceptable quality level (AQL), the lot tolerance percent defective (LTPD), the probability of rejecting a high quality lot (alpha) and the probability of accepting a low quality lot (beta). TRUE


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50. AQL stands for accepting questionable lots in production quality management. FALSE


51. LTPD in acceptance sampling stands for "lots of tolerance for parts defective." FALSE


52. The Greek letter alpha is associated with consumer's risk. FALSE


53. The probability associated with rejecting a high quality lot is denoted in acceptance sampling with the Greek letter alpha. TRUE


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54. The probability associated with accepting a low quality lot is denoted in acceptance sampling with the Greek letter alpha. FALSE


55. The producer's risk associated with rejecting a high quality lot is denoted in acceptance sampling with the Greek letter beta. FALSE


56. Total, one-hundred percent, inspection can never be cost justified. FALSE


57. One-hundred percent inspection is justified when the cost of inspection is not very much. FALSE


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58. Sampling plans are generally displayed graphically through the use of operating characteristic (OC) curves. TRUE


59. The capability index (Cpk) calculates the percentage of items being produced within specifications. FALSE


60. The capability index (Cpk) indicates the position of the mean and tails of a processes variance relative to design specifications. TRUE

AACSB: AnalyticDifficulty: MediumLearning Objective: 4Taxonomy: KnowledgeTopic: Statistical Quality Control

61. Standard practice in statistical process control for variables is to set control limits so that 95 percent of the sample means will fall within the UCL and the LCL. FALSE

AACSB: AnalyticDifficulty: MediumLearning Objective: 5Taxonomy: AnalysisTopic: Process Control Procedures

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62. In variables sampling the actual measurements of the variable observed are used regardless of whether the unit is good or bad. TRUE


Multiple Choice Questions

63. The philosophical leaders of the quality movement, Philip Crosby, W. Edwards Deming, and Joseph M. Juran had the same general message about what it took to achieve outstanding quality. Which of the following was not part of that message? A. Quality is freeB. Leadership from senior managementC. Customer focusD. Total involvement of the workforceE. Continuous improvement


64. The philosophical leaders of the quality movement, Philip Crosby, W. Edwards Deming, and Joseph M. Juran had the same general message about what it took to achieve outstanding quality. Which of the following was part of that message? A. Fourteen steps for quality managementB. Quality is freeC. Customer focusD. Zero defectsE. Six-sigma


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65. An analytical tool used in six-sigma quality improvement programs is which of the following? A. LeadershipB. Continuous improvementC. Quick responseD. Partnership developmentE. Checksheets


66. Which of the following is not an analytical tool used in six-sigma quality improvement programs? A. Run chartsB. Pass chartsC. Cause-and-effect diagramsD. FlowchartsE. Pareto charts


67. A flow chart as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control


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68. A fishbone diagram as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control


69. An opportunity flow diagram as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control


70. A Pareto chart as part of a six-sigma quality improvement process might be found in which DMAIC category? A. DefineB. MeasureC. AnalyzeD. ImproveE. Control


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71. Which of the following is an analytical tool used in six-sigma quality improvement programs? A. LeadershipB. Pareto ChartsC. Management by factD. Continuous improvementE. Kaizen


72. Which of the following is not an analytical tool used in six-sigma quality improvement programs? A. FlowchartsB. Run chartsC. Control chartsD. Pareto analysisE. Tendency analysis


73. Failure mode and effect analysis is used in six-sigma projects. It involves which of the following? A. Closely examining each rejected part to determine the causeB. A careful sampling planC. Calculating a risk priority number for each possible failureD. Reporting the effect each failure has had on a customerE. Multivariate testing


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74. Design of experiments is a statistical methodology often used in six-sigma projects. It aims to accomplish which of the following? A. Keep careful track of the occurrences of each possible defectB. Determine the cause and effect relationships between process variables and outputC. Report defects to management on a Pareto chartD. Carefully change each individual process variable until the cause of a defect is foundE. Eliminate defects by finding out who or what is causing them


75. The Malcolm Baldrige award selection process helps improve quality and productivity by which of the following means? A. Stimulating foreign based suppliers of American companies to improve qualityB. Reporting quality levels among American firmsC. Identifying American firms with the most difficult quality problemsD. Providing feedback to applicants by the examinersE. Helping Baldrige award winners increase their sales


76. Which of the following are eligible companies to be considered for the Baldrige award? A. Auditing firmsB. Offshore suppliers to U. S. companiesC. Firms operating only outside the U. S.D. State Government agenciesE. None of the above


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77. Which of the following are not eligible to be considered for the Baldrige Award? A. Small businessesB. Health care organizationsC. Educational institutionsD. State highway patrol organizationsE. Nuclear power plants


78. The primary purpose of the Malcolm Baldrige National Quality Award is which of the following? A. To encourage the spread of statistical quality controlB. To improve human resource development and management in manufacturingC. To improve competitiveness of American firmsD. To prove that American firms were competitive in qualityE. To emphasize the use of quantitative methods in process management


79. The Grading Criteria of the Baldrige Award for total quality management includes which of the following? A. Future plansB. Information and analysisC. StandardizationD. ControlE. None of the above


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80. The Malcolm Baldrige National Quality Award is given to organizations that have done which of the following? A. Instituted a six-sigma approach to total quality controlB. Demonstrated a high level of product qualityC. Demonstrated outstanding quality in their products and processesD. Have a world-class quality control functionE. Most significantly improved their product quality levels


81. Which of the following is not a category reported in applying for the Baldrige Award? A. Corporate leadershipB. Use of statistical quality control toolsC. Business resultsD. Consumer and market focusE. Strategic planning


82. The dimension of design quality that concerns the sensory characteristics of the product is which of the following? A. FeaturesB. ServiceabilityC. Perceived qualityD. ReputationE. Aesthetics


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83. The dimension of design quality that concerns the consistency of performance over time or the probability of failing is which of the following? A. ResponseB. ServiceabilityC. ReliabilityD. ReputationE. Perceived quality


84. The dimension of design quality that concerns secondary characteristics is which of the following? A. FeaturesB. ServiceabilityC. ReliabilityD. ReputationE. Perceived quality


85. Which of the following is a dimension of design quality? A. PriceB. FeaturesC. ColorD. WeightE. Quality at the source


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86. Which of the following is a dimension of design quality? A. AestheticsB. PriceC. Quality at the sourceD. DistributionE. Leadership


87. Which of the following is a basic assumptions that justify an analysis of the costs of quality? A. Failures are causedB. Prevention is more expensiveC. Performance can be learnedD. Rules of thumb don't always workE. Appraisal costs are less than prevention costs


88. A cost of quality classification is which of the following? A. Material costsB. Prevention costsC. Variable overheadD. Direct laborE. Inventory costs


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89. Which of the following is the cost of quality classification for costs such as scrap, rework, or repair? A. Appraisal costsB. Prevention costsC. External failure costsD. Internal failure costsE. Rework and wastage


90. Which of the following is the cost of quality classification for costs such as inspection, testing, and other tasks to ensure that the product or process is acceptable? A. Appraisal costsB. Prevention costsC. External failure costsD. Internal failure costsE. Checking costs


91. Which of the following is the cost of quality classification for costs such as defects that pass through the system, such as customer warranty replacements, loss of customer or goodwill, handling complaints, and product repair? A. Appraisal costsB. Prevention costsC. External failure costsD. Customer return costE. Workmanship costs


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92. Which of the following tools uses a graphical representation of the production process to suggest potential sources of process variation? A. Process flow diagramB. Check sheetC. Pareto chartD. HistogramE. Run chart


93. In monitoring process quality we might use which of the following statistics? A. Absolute valuesB. Percentage deviation from tolerance centersC. "k" values for the sample meanD. Logarithmic control intervalsE. Difference between the highest and lowest value in a sample


94. You have just used the capability index (Cpk) formulas to compute the two values "min [2, 2.5]." Which of the following is the proper interpretation of these numbers? A. The true capability index value is 2.5B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. The true capability index value is between 2 and 2.5

AACSB: AnalyticDifficulty: MediumLearning Objective: 4Taxonomy: AnalysisTopic: Statistical Quality Control

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95. You have just used the capability index (Cpk) formulas to compute the two values "min [1, 1]." Which of the following is the proper interpretation of these numbers? A. The true capability index value is exactly 1B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. None of the above

AACSB: AnalyticDifficulty: MediumLearning Objective: 4Taxonomy: AnalysisTopic: Statistical Quality Control

96. You have just used the capability index (Cpk) formulas to compute the two values "min [1.5, 1]." Which of the following is the interpretation of these numbers? A. The true capability index value is 1B. The mean of the production process has shifted to the left of the design limitsC. The mean of the production process has shifted to the right of the design limitsD. The mean has not shifted at allE. The true capability index value is between 1.5 and 1


97. Quality control charts usually have a central line and upper and lower control limit lines. Which of the following is not a reason that the process being monitored with the chart should be investigated? A. A large number of plots are close to the upper or lower control linesB. Erratic behavior of the plotsC. A single plot falls above or below the control limitsD. A change in raw materials or operatorsE. A run of five above the central line


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98. Quality control charts usually have a central line and upper and lower control limit lines. Which of the following is a reason that the process being monitored with the chart should be investigated? A. A single plot falls above or below the control limitsB. Normal behaviorC. A large number of plots are on or near the central lineD. No real trend in any directionE. A change in raw materials or operators


99. If there are 120 total defects from 10 samples, each sample consisting of 10 individual items in a production process, which of the following is the fraction defective that can be used in a "p" chart for quality control purposes? A. 120B. 10C. 8D. 1.2E. 0.8


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100. If there are 400 total defects from 8 samples, each sample consisting of 20 individual items in a production process, which of the following is the fraction defective that can be used in a "p" chart for quality control purposes? A. 400B. 160C. 2.5D. 1.0E. 0.4


101. You want to determine the upper control line for a "p" chart for quality control purposes. You take several samples of a size of 100 items in your production process. From the samples you determine the fraction defective is 0.05 and the standard deviation is 0.01. If the desired confidence level is 99.7 percent, which of the following is the resulting UCL value for the line? A. 0.39B. 0.08C. 0.06D. 0.05E. None of the above


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102. You want to determine the lower control line for a "p" chart for quality control purposes. You take several samples of a size of 50 items in your production process. From the samples you determine the fraction defective is 0.006 and the standard deviation is 0.001. If the desired confidence level is 99.7 percent, which of the following is the resulting LCL value for the line? A. 0.0B. 0.002C. 0.003D. 0.004E. None of the above


103. You want to determine the control lines for a "p" chart for quality control purposes. If the desired confidence level is 99 percent, which of the following values for "z" would you use in computing the UCL and LCL? A. 0.99B. 2C. 2.58D. 3E. None of the above


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104. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 2,500, the number of samples is 100, and the sample size is 50, which of the following would be the standard deviation used in developing the control lines? A. 0.4900B. 0.2499C. 0.1556D. 0.0707E. 0.02499

AACSB: AnalyticDifficulty: MediumLearning Objective: 5Taxonomy: KnowledgeTopic: Process Control Procedures

105. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 560, the number of samples is 70, and the sample size is 80, which of the following would be the standard deviation used in developing the control lines? A. 0.9000B. 0.4556C. 0.0335D. 0.0011E. 0.0112


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106. For which of the following should we use a "p" chart to monitor process quality? A. Defective electrical switchesB. Errors in the length of a pencilC. Weight errors in cans of soupD. Temperature of entrees in a restaurantE. Letter grades on a final examination


107. For which of the following should we use a "p" chart to monitor process quality? A. The dimensions of brick entering a kilnB. Lengths of boards cut in a millC. The weight of fluid in a containerD. Grades in a freshman "pass/fail" courseE. Temperatures in a classroom


108. With which of the following should we use an "X-bar" chart based on sample means to monitor process quality? A. Grades in a freshman "pass/fail" courseB. Tire pressures in an auto assembly plantC. Vehicles passing emissions inspectionD. Computer software errorsE. Number of units with missing operations


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109. Which of the following should we use an "R" chart to monitor process quality? A. Grades in a freshman "pass/fail" courseB. Tire pressures in an auto assembly plantC. Vehicles passing emissions inspectionD. Computer software errorsE. Number of units with missing operations


110. Which of the following should we use an "R" chart to monitor process quality? A. Weighing trucks at a highway inspection station to determine if they are overloadedB. Deciding whether an airliner has sufficient fuel for its tripC. Student grades measured from 1 to 100D. Determining whether vehicles from a motor pool will runE. Determining the accuracy of a forecast of "snow"


111. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99.7 percent, and the average of the sample means is 24. Which of the following is your UCL? A. 36B. 24C. 12D. 4E. None of the above


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112. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99 percent, and the average of the sample means is 20. Which of the following is your LCL? A. 36B. 24C. 9.68D. 16.79E. 30.32


113. You want to develop a three-sigma "R" chart. You know the average range is 5 based on several samples of size 10. Which of the following is the resulting UCL? A. 20.9B. 8.9C. 7.02D. 5E. 3.1


114. You want to develop a three-sigma "R" chart. You know the average range is 12 based on several samples of size 6. Which of the following is the resulting LCL? A. 20.0B. 18.3C. 7.02D. 5.6E. 0.0


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115. If you are going to develop an "X-bar" chart based on range statistics and you are using a sample size of 12 for your charting purposes. Which of the following is the A2 factor for the "X-bar" chart? A. 0.37B. 0.31C. 0.27D. 0.22E. .18


116. If you are going to develop an "R" chart based on range statistics and you are using a sample size of 9 for your charting purposes. Which of the following is the lower control limit D3 factor for the chart? A. 0.08B. 0.14C. 0.18D. 0.22E. 0.29


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117. If you are going to develop an "R" chart based on range statistics and you are using a sample size of 15 for your charting purposes. Which of the following is the upper control limit D4 factor for the chart? A. 1.65B. 1.70C. 1.76D. 1.87E. 1.92



118. The National Quality Award in the United States is named ______________________. The Malcolm Baldrige National Quality Award


119. The expenditures related to achieving product or service quality including the costs of appraisal and prevention of defects are called ______________________. Cost of quality


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120. ISO-9000 standards were developed to ______________________ help companies document that they are maintaining an efficient quality system. (Text, page 140)


121. Six-sigma programs believe that each step in a process is an opportunity to produce defects. These programs seek to reduce defects by working on processes to reduce ______________________. Variance


122. If the fraction defective is 0.12 based on a sample size of 16, the standard deviation to be used when constructing a "p" chart is ______________________. 0.081


123. If the fraction defective is 0.4 based on a sample size of 100, the standard deviation used in constructing the "p" chart is ______________________. 0.049


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124. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 2,000, the number of samples is 100, and the sample size is 50, the standard deviation used in developing the control lines would be ______________________. 0.0693


125. You want to determine the control lines for a "p" chart for quality control purposes. If the total number of defects from all samples is 560, the number of samples is 70, and the sample size is 80, the standard deviation used in developing the control lines would be ______________________. 0.335


126. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99.7 percent, and the average of the sample means is 24. The UCL is ______________________. 36


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127. You are developing an "X-bar" chart based on sample means. You know the standard deviation of the sample means is 4, the desired confidence level is 99 percent, and the average of the sample means is 20. The LCL is ______________________. 9.68


128. You want to develop a three-sigma "R" chart. You know the average range is 5 based on several samples of size 10. The resulting UCL is ______________________. 8.9


129. You want to develop a three-sigma "R" chart. You know the average range is 12 based on several samples of size 6. The resulting LCL is ____________________. Zero


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Short Answer Questions

130. The symbol designating the capability index is ______________________.

Cpk



131. All else being equal, the magnitude of the effect of lot size on sample size is ______________________. negligible (or very small)


132. You have 75 total defects from 100 different samples of 15. The value of "p" is ______________________. 0.05


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133. Lots are defined as low quality when the percentage of defective units is greater than ______________________. Lot Tolerance Percent Defective (LTPD)


Essay Questions

134. What is the difference between the concepts of design quality and conformance quality?

Refer to the text, page 136-137. Design quality refers to the specifications that are drawn up at the product design stage which define the inherent value of the product in the marketplace. For example, are we designing a service package for a cheap roadside diner or for an exclusive French restaurant? Are we designing a set of skis for the advanced professional or for the fledgling beginner? Conformance quality relates to the degree to which the product or service design specifications are met.

AACSB: AnalyticDifficulty: MediumLearning Objective: 2Taxonomy: UnderstandingTopic: Quality Specifications and Quality Costs

135. What does it mean when we say that a process is capable?

From the text on page 150, "a process is capable when the mean and standard deviation of the process are operating such that the upper and lower control limits are acceptable relative to the upper and lower specification limits."


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136. Explain the difference between producer's risk and consumer's risk in acceptance sampling.

Producer's risk (alpha) is the probability of rejecting a high quality lot while consumer's risk (beta) is the probability of accepting a low-quality lot. See text, page 164.


137. What is the difference between statistical quality control and statistical process control?

Process control is concerned with monitoring quality while the product or service is being produced. (text, p. 154). Statistical process control involves taking samples of output to determine whether the process is producing product within the desired range. Statistical quality control is designed to evaluate the product's conformance to specifications set during the design of the products or services being produced. (text, p.146). Thus, SQC includes the idea of SPC but also includes checking quality levels of products and services after production is complete.

AACSB: AnalyticDifficulty: HardLearning Objective: 2Taxonomy: SynthesisTopic: Quality Specifications and Quality Costs

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Chap 006

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