Question 1

Which of the following describes the purpose of acceptance sampling (defect-detection)?
A) Computer chips received by a computer maker are sampled before the shipment is accepted or rejected.
B) The manufacturer of pocket knifes samples its process at three stages before allowing the pocket knives to be assembled.
C) The manufacturer of gypsum wallboard subjects samples of its fireproof version to tests in controlled fire situations.
D) Each worker is responsible for the quality of his/her output and tests each item before sending them on to packaging.
E) A quality checksheet for each division is completed before the product is released to retailers.

Accepted Answer

Acceptance sampling, also known as defect-detection, is a method of sampling a batch or lot of products before accepting or rejecting it. In option A, computer chips are being sampled before the shipment is accepted or rejected, which is the purpose of acceptance sampling. The other options describe different quality control methods, but not specifically acceptance sampling.

Question 2

When the only sources of variation in a production process are caused by chance,and random variation remains within acceptable limits,the process is said to be:
A) stable.
B) in statistical control.
C) out of control.
D) out of luck.
E) Both A and B since they are the same.

Accepted Answer

When a production process's variation is only due to chance and this random variation stays within acceptable limits, the process is considered to be stable and in statistical control. Both terms describe a process where the output is predictable and consistent, hence "Both A and B" is correct.

Question 3

Individual units can have higher quality than others,even while meeting traditional specifications.Deviations from the target lead to lower and lower quality of the unit.This concept is associated with a:
A) cause and effect diagram.
B) process flow chart.
C) check sheet.
D) Taguchi method.
E) Pareto diagram.

Accepted Answer

This concept is associated with the Taguchi method. The Taguchi method focuses on reducing the variation in process and improving the quality of individual units by considering the impact of different factors and their interactions on the final product. It emphasizes the importance of designing products and processes that are robust to variations in factors such as materials, machines, and human factors, in order to achieve higher quality and customer satisfaction.

Question 4

A random sample of 100 rods from a process with a mean of 20 feet produced a sample mean of 20.01 feet and a standard deviation of 0.015.This difference between the process mean and the sample mean is likely to be:
A) assignable variation.
B) special-cause variation.
C) random variation.
D) homoscedasticity.
E) costs of attrition.

Accepted Answer

The small difference between the process mean and the sample mean (0.01 feet) is within the realm of random variation and is not large enough to be considered special-cause or assignable variation. Homoscedasticity refers to the equal variance of a variable across different levels, which is not relevant here. Costs of attrition are also not relevant to this scenario.

Question 5

Variations in process output that can usually be identified and eliminated without changing the process are:
A) assignable variations.
B) chance variations.
C) out of control variations.
D) random variations.
E) All of these.

Accepted Answer

Assignable variations, also known as special cause variations, are variations that can be identified and eliminated by identifying their root causes and making changes to the process. This is in contrast to chance variations (also called common cause variations or random variations) which cannot be eliminated without making changes to the process itself. Out of control variations refer to situations where the process is not stable, and may include both assignable and chance variations. Random variations refer specifically to chance or common cause variations.

Question 6

Variations in process output that are caused by specific events or factors that are frequently temporary such as machine malfunction are:
A) assignable variations.
B) chance variations.
C) out of control variations.
D) random variations.
E) All of these.

Accepted Answer

Assignable variations are caused by specific events or factors that are often temporary, such as machine malfunctions or operator errors. These variations can be traced back to a specific cause and can be eliminated or controlled. Chance variations, also known as random or common cause variations, are inherent in any process and cannot be eliminated completely. Out of control variations refer to any variation that falls outside of the control limits and indicates that the process is not in a state of statistical control.

Question 7

Which of the following describes the purpose of statistical process control (defect-prevention)?
A) A consumer buys a TV and plugs it in.It doesn't work and she returns it.
B) A soft drink company samples its product at 25 retail establishments to determine if the canner's mixture meets the soft drink company's standard.
C) The Army purchases hammers and tests 10 of them before accepting the entire shipment.
D) Computer chips received by a computer maker are sampled before the shipment is accepted or rejected.
E) The manufacturer of pocket knifes samples its process at three stages before allowing the pocket knives to be assembled.

Accepted Answer

The purpose of statistical process control (SPC) is to prevent defects by identifying and correcting process variations before they result in nonconforming products. Option E describes how the manufacturer of pocket knives uses SPC by sampling the process at three stages, ensuring that any variations are identified and corrected before the final product is assembled. Options A, B, C, and D describe quality control measures that are reactive rather than preventative, meaning they only identify defects after they have occurred.

Question 8

Which of the following relates to costs of non-conformance?
A) Coordination with suppliers.
B) Defective products that reduce goodwill.
C) Periodic customer surveys.
D) Worker involvement.
E) Revisions to product design.

Accepted Answer

Costs of non-conformance refer to the costs incurred due to producing defective products that do not meet the required quality standards. Such products reduce customer satisfaction, damage the company's reputation, and lead to loss of goodwill.

Question 9

In statistical process control (SPC),a Type I error occurs if we conclude that the process is:
A) in control when in fact it is not.
B) out of control when in fact it is not.
C) in control when this is really true.
D) out of control when this is really true.
E) None of these.

Accepted Answer

A Type I error in SPC occurs when we incorrectly conclude that the process is out of control, when in fact it is not. This means that we may take unnecessary actions to try to fix the process when it is actually functioning within acceptable limits.

Question 10

The TQM philosophy of defect prevention has quality integrated throughout the organizational structure and central to corporate thinking in all matters.

Accepted Answer

The TQM philosophy of defect prevention emphasizes the importance of quality throughout the organizational structure and promotes a proactive approach to preventing defects rather than merely discovering and correcting them after the fact. It is a comprehensive approach that involves all aspects of the organization and is central to corporate thinking in all matters. Therefore, the statement is true.

Question 11

Variations in process output that are caused by events that in general cannot be eliminated without changing the process are:
A) assignable variations.
B) random variations.
C) out of control variations.
D) None of these.
E) All of these.

Accepted Answer

These types of variations are known as random variations, which occur naturally and cannot be traced to a specific cause or source.

Question 12

An electronics part manufacturer reprimanded an employee.The number of defective parts produced by the employee increased.The increase in the number of defective parts is probably an example of:
A) assignable variation.
B) common-cause variation.
C) random variation.
D) homoscedasticity.
E) costs of attrition.

Accepted Answer

The increase in the number of defective parts is likely due to assignable variation, which is caused by specific identifiable factors such as the reprimand given to the employee. Common-cause variation refers to natural variation that is inherent in the process, while random variation is unpredictable and cannot be attributed to any specific cause. Homoscedasticity refers to the assumption of equal variance in a statistical model, which is not relevant to this scenario. Costs of attrition refer to the expenses involved in employee turnover, which is not directly related to the increase in defective parts.

Question 13

Which of the following statements is correct with regard to random variation?
A) It occurs as the result of chance
B) It is inherent in practically any process
C) It leads to random variation in the product
D) It can often be reduced by using more expensive machines or materials
E) All of these statements are correct

Accepted Answer

All of these statements are correct.

Random variation occurs due to chance and is present in most processes. It can lead to variation in the product, and sometimes this variation can be reduced by using more precise machines or better materials.

Question 14

When no point lies outside the control limits of a chart,we conclude that:
A) variation in the process is caused by assignable causes and there is enough evidence to infer that the process is in statistical control.
B) variation in the process is caused by chance and there is enough evidence to infer that the process is out of control.
C) variation in the process is caused by chance and there is not enough evidence to infer that the process is out of control.
D) variation in the process is caused by assignable causes and there is not enough evidence to infer that the process is out of control.
E) None of these.

Accepted Answer

When no point lies outside the control limits of a chart, it indicates that the variation in the process is likely due to random (chance) causes rather than specific (assignable) causes, and there is not enough evidence to declare the process out of control. This suggests the process is operating within expected variability limits.

Question 15

Which of the following relates to costs of conformance?
A) Defective products that reduce goodwill.
B) Poor quality requiring product recalls.
C) Periodic worker training.
D) Poor quality requiring warranty expenses.
E) Product liability lawsuits.

Accepted Answer

Costs of conformance are expenses incurred to ensure products are made correctly the first time. Periodic worker training is a measure taken to ensure workers are properly equipped with knowledge and skills to do their job correctly, thus reducing production errors and overhead costs associated with fixing mistakes.

Question 16

Although both statistical process control and acceptance sampling make inferences on the basis of samples,
A) acceptance sampling involves inspection of a sample of products during the production run.
B) SPC uses sampled products to make inferences about the process from which they came.
C) acceptance sampling uses sampled products to make inferences about a larger population of the products.
D) Both B and C
E) All of the above statements are true.

Accepted Answer

SPC uses sampled products to make inferences about the process from which they came, while acceptance sampling uses sampled products to make inferences about a larger population of products. Additionally, acceptance sampling involves inspection of a sample of products during the production run. Therefore, both statements B and C are true.

Question 17

Much of the emphasis in TQM is on understanding and reducing variation within the process through which the product is produced,and samples of output are used in reaching inferences about the stability of the process.

Accepted Answer

This statement accurately reflects a key aspect of TQM, which involves analyzing and improving the process by which a product is made in order to reduce variability and improve quality. Samples of output are often used to monitor the process and identify areas for improvement.

Question 18

A company maintains a minimum of inventory of parts to keep its production process going.If there is any interruption in the delivery of quality parts,production stops until quality is restored.This company is using:
A) competitive benchmarking.
B) acceptance sampling.
C) just-in-time manufacturing.
D) random variation.
E) a quality circle.

Accepted Answer

The company is using just-in-time manufacturing which is a lean manufacturing approach where inventory is kept to a minimum and parts and materials are delivered just in time for production. This reduces waste and cuts costs, but also means that interruptions in the delivery of quality parts can lead to production stoppages.

Question 19

Perry Company,a variety store,sends a team of five executives to Wal-Mart headquarters in Bentonville,Arkansas,to observe the distribution and logistics practices so that Perry Company can improve in these areas.This firm is engaging in:
A) worker training.
B) statistical process control.
C) a quality circle.
D) competitive benchmarking.
E) acceptance sampling.

Accepted Answer

Perry Company is engaging in competitive benchmarking by observing the practices of another company to improve their own distribution and logistics practices. Worker training, statistical process control, quality circles, and acceptance sampling are all different methods of improving internal processes, not necessarily through benchmarking.

Question 20

A popular and important tool for applying TQM is statistical process control,where sampled products are used in making inferences about the process from which they came.

Accepted Answer

Statistical process control is a key tool in implementing TQM, where products are sampled and analyzed to make inferences about the underlying process.

Quiz 20: Total Quality Management

Which of the following describes the purpose of acceptance sampling (defect-detection) ?

When the only sources of variation in a production process are caused by chance,and random variation remains within acceptable limits,the process is said to be:

Individual units can have higher quality than others,even while meeting traditional specifications.Deviations from the target lead to lower and lower quality of the unit.This concept is associated with a:

A random sample of 100 rods from a process with a mean of 20 feet produced a sample mean of 20.01 feet and a standard deviation of 0.015.This difference between the process mean and the sample mean is likely to be:

Variations in process output that can usually be identified and eliminated without changing the process are:

Variations in process output that are caused by specific events or factors that are frequently temporary such as machine malfunction are:

Which of the following describes the purpose of statistical process control (defect-prevention) ?

Which of the following relates to costs of non-conformance?

In statistical process control (SPC) ,a Type I error occurs if we conclude that the process is:

The TQM philosophy of defect prevention has quality integrated throughout the organizational structure and central to corporate thinking in all matters.

Variations in process output that are caused by events that in general cannot be eliminated without changing the process are:

An electronics part manufacturer reprimanded an employee.The number of defective parts produced by the employee increased.The increase in the number of defective parts is probably an example of:

Which of the following statements is correct with regard to random variation?

When no point lies outside the control limits of a chart,we conclude that:

Which of the following relates to costs of conformance?

Although both statistical process control and acceptance sampling make inferences on the basis of samples,

Much of the emphasis in TQM is on understanding and reducing variation within the process through which the product is produced,and samples of output are used in reaching inferences about the stability of the process.

A company maintains a minimum of inventory of parts to keep its production process going.If there is any interruption in the delivery of quality parts,production stops until quality is restored.This company is using:

Perry Company,a variety store,sends a team of five executives to Wal-Mart headquarters in Bentonville,Arkansas,to observe the distribution and logistics practices so that Perry Company can improve in these areas.This firm is engaging in:

A popular and important tool for applying TQM is statistical process control,where sampled products are used in making inferences about the process from which they came.