MGMT 480 CHAPTER 16

Common cause variation a. Cannot be explained except in an aggregate sense b. Is easily detectable with statistical methods and control charts c. Cannot be reduced through better technology, process design, or training d. Is the responsibility of the workers who run the processes

A

Historically, the average proportion of defective bars has been 0.015. Samples of 100 bars each are taken. Construct a p-chart using z = 3. Suppose a sample had 0.044 defectives. What would you do? a. Nothing; it appears to be random variation. b. Look for assignable causes. c. Delete the sample with 0.044 defects and take another sample that is better. d. None of these choices

A

Quality at the source means that quality is controlled by a. People responsible for the work b. Quality control managers c. Front line supervisors d. Top management

A

Which of the following is not a component of a control system? a. Statistical sampling b. Measures of actual performance c. Goals or standards d. Comparison of actual performance with standards or goals for corrective action if necessary

A

Which of the following suggests a process that is not in control? a. Points follow a smooth pattern from the lower control limit to the upper control limit b. The number of points above and below the center line is about the same c. Points fall randomly above and below the center line d. No points are outside the control limits

A

p-charts a. Are used for the fraction of non-conforming items b. Count the number of nonconformances per unit c. Use continuous metrics d. Can have negative lower limits

A

Evaluating the trade-offs between the costs of detecting and replacing a defective part or allowing it to continue on through the production process is related to a. Supplier certification and management b. In-process control c. Finished goods control d. Statistical process control

B

If no special causes affect the output of a process, we say that the process is ____; when special causes are present, the process is said to be ____. a. Qualified; not qualified b. In control; out of control c. Capable; not capable d. Certified; not certified

B

Which of the following is most closely related to Statistical Process Control (SPC)? a. Removing common causes of variation b. Removing special causes of variation c. Removing all causes of variation d. Computing process capability

B

Which one of the following statements is true? a. Common cause variation arises from external sources that are not inherent in the process and is where statistical quality control methods are most useful. b. If the metric is discrete, a p- or c-chart is normally used. c. Statistical process control is not used in hospitals due to the high liability costs. d. Statistical process control charts are used when trying to monitor and control 5- and 6-sigma quality levels.

B

c-charts a. Are used for the fraction of non-conforming items b. Count the number of nonconformances per unit c. Use continuous metrics d. Can have negative lower limits

B

A bottling process sometimes results in overfills or underfills. Overfills are especially damaging to the equipment. Which process capability index would this company most want to monitor? a. Cp b. Cpl c. Cpu d. Cpk

C

A supplier is producing a machined part for the transmission of your vehicle. The upper specification limit is 0.125 cm and the lower specification limit is 0.085. The process standard deviation for the process that makes this part is 0.008 and the process average is 0.105. What conclusion can be drawn from these process capability data? a. The process is centered and capable. b. The process is not centered and capable. c. The process is centered and not capable. d. The process is not centered and not capable.

C

In the 1:10:100 Rule, which of the following would be correct? a. If a defect or service error is identified and corrected at the design stage, it might cost $100 to fix. b. If a defect or service error is identified and corrected at the production process stage, it might cost $100 to fix. c. If a defect or service error is identified and corrected after it reaches the customer, it might cost $100 to fix. d. If a defect or service error is identified and corrected at the design stage, it might cost $1 $10 $100 = $1,000 to fix.

C

Ritz-Carlton Hotel Company uses which one of the following methods to control quality? a. R-bar and x-bar control charts to monitor customer complaints. b. The 1:10:100 rule for goods quality only c. Self-control of the individual employee based on their spontaneous behavior. d. The process capability index for all goods and services provided by the hotel.

C

Statistical calculations will show that if p = .01, then the sample size needed to have at least a 95% chance of finding at least one nonconformance is a. 30 b. 100 c. 300 d. 1,000

C

Testing whether a computer boots up the first time is an example of a. Supplier certification and management b. In-process control c. Finished goods control d. Statistical process control

C

Which of the following is not related to a continuous metric? a. Measured as the degree of conformance to a specification b. x-bar and R-charts c. p-chart d. Time

C

1. Common cause variation is a. Controllable at the sources b. Called assignable cause c. Can be reduced by statistical process control methods d. The responsibility of management

D

Honda wants to monitor the number of blemishes (scratches, blisters, etc.) on the fenders of its cars using a statistical process control chart. The most appropriate type of SPC chart is a. x-bar. b. R-bar chart. c. Cpk chart d. c-chart

D

Regarding special cause variability, all are true except a. Disrupt the random patterns of common cause variation b. Arises from external sources that are not inherent in the process c. Appear sporadically d. Hard to detect using statistical methods

D

The center line (p-bar) for a p-chart is 0.50 with an UCL = 0.70 and a LCL = 0.35. The results of the next eight sample means are 0.45, 0.60, 0.39, 0.44, 0.48, 0.53, 0.54, and 0.61. What would you do? a. Nothing; the process is in control. b. increase the sample size to get a better measure. c. investigate assignable causes because four observations are above the center line. d. investigate assignable causes because there is a bad trend (run).

D

The upper and lower specification limits for a component are 4.20 and 4.30 ounces, respectively. The process standard deviation is .02, and the process average is 4.24 ounces. Which one of the following statements is true? a. The Cp index indicates the process is centered. b. The Cp index indicates the process is not centered. c. The Cpk index indicates the process is centered. d. The Cpk index indicates the process is not centered.

D

Which is not related to a discrete metric? a. Counting b. Visual inspection c. Good or bad d. Time

D