Which type of control chart should be used when it is possible to have

more than one mistake per item?

  p-chart
  
R-chart
  
c-chart
  
x-bar chart
  

One type of control chart for attributes is a

  R-chart.
  
p-chart.
  
x-bar chart.
  
CPK chart.
  

C-charts are based on the

  binomial distribution.
  
normal distribution.
  
Poisson distribution.
  
Erlang distribution.
  

If a sample of parts is measured and the mean of the sample

measurements is outside the control limits
  the process is out of control and the cause can be established.
  
The process variance must also be in control.
  
the process is within the established control limits with only natural causes of
   variation.
the process is in control, but not capable of producing within the established
   control limits.

Process capability
  cannot be measured.
  
exists when CPK is less than 1.0.
  
exists when the process is perfectly centered.
  
means that the natural variation of the process must be small enough to produce
   products that meet the standard.

The object of a statistical process control (SPC) system is to

  eliminate natural variation.

  
provide a signal when assignable variations are present.
  
provide a signal when natural variations are present.
  
assess the customer expectations.
  

The R-chart

  is used to indicate gains or losses in uniformity.

  
is used to measure changes in the central tendency.
  
is always in control if the X-bar chart is in control.
  
generally uses control limits set at plus or minus 2 standard deviations of the
   distribution, rather than plus or minus 3 which is commonly used on the X-bar
chart.

In acceptance sampling, the producer's risk is the risk of having a

  good lot rejected.

  
good lot accepted.
  
bad lot rejected.
  
bad lot accepted.
  

Twenty samples of size 5 are taken from a stable process. The average
means of the sample means is 42.5, and the average range of the
samples is 1.5. What is the UCL for the X-bar chart? 
**NOTE** Table S6.1, Factors for Computing Control Chart Limits, is
available in the Hint portion of this question.
  47.0
  
42.5
  
3.17
  
43.37
  

Twenty samples of size 5 are taken from a stable process. The average
means of the sample means is 42.5, and the average range of the
samples is 1.5. What is the UCL for the R-chart? 
**NOTE** Table S6.1, Factors for Computing Control Chart Limits, is
available in the Hint portion of this question.
  0.00
  
43.37
  
3.17
  
1.5
  

Twenty samples of size 100 are taken. The total number of defective
items is 75. What is the UCL of the 3-sigma (z=3) p-chart?
  .094
  
.0375
  
0.793
  
.165
  

A customer service hotline has received an average of 7 complaints a

day for the last 25 days. What type of control chart should be used to
monitor this hotline?
  X-bar chart
  
p-chart
  
c-chart
  
R-chart
  
 For the last 30 days, the number of mistakes on the daily report has
averaged 4.5. What would the UCL be if a 3-sigma c-chart was
constructed?
  7.5
  
2.12
  
10.86
  
18
  

A bottling company runs a filling process that should fill bottles with 12
plus or minus 0.04 ounces. A capability study reveals that the process
mean is 12 ounces and the standard deviation is 0.01 ounces. What is
the capability of the bottling process?
  0.75
  
1.5
  
1.33
  
0.67
  

A manufacturing engineer is designing a process that must be able to

produce a shaft with a diameter of 2.5 cm plus or minus 0.01 cm. If the
process capability must be 1.5, what is the maximum process standard
deviation?
  0.00222
  
2.49 - 2.51
  
0.0133
  
0.02
  

Which is the best statement regarding an operating characteristic

curve?
  As the fraction defective decreases, the probability of accepting the lot also
   decreases.
As the lot tolerance percent defective decreases, the consumer's risk also
   decreases.
As the fraction defective increases, the probability of accepting the lot also
   increases.
 As the AQL decreases, the producer's risk also decreases.
  

A box of 1000 parts is subjected to an acceptance sampling plan that

examines only 50 parts. The actual fraction defective in the box is 0.02
and the sampling plan has a 0.53 probability of accepting a box of this
quality. What is the average outgoing quality for this scenario?
  0.02
  
0.01
  
0.53
  
0.51
  

1. Using the terminology of statistical control, the variation within a stable system
    a. is random variation. 
    b. results from common causes.
    c. is predictable within a range. 
    d. a and b. 
    e. all of the above.

2. Using the terminology of statistical control, the variation outside the control limits
on an X-bar or range chart
    a. is viewed as uncontrollable.
    b. is assumed to have been caused by special or assignable causes.
    c. indicates that the system is probably out of control.
    d. b and c.
    e. all of the above.

3. One type of error a manager can make is to blame a worker for an undesirable
variation that is caused by the system. Refer to this as a type I error. Another type of
error a manager can make is to blame the system when a worker caused the
undesirable variation. Refer to this as a type II error. If a company changed the basis
for the upper and lower limits on a control chart from three standard deviations to two
standard deviations
    a. the number of type I errors would increase.
    b. the number of type II errors would increase.
    c. the number of both types of errors would increase.
    d. the number of both types of errors would decrease.
    e. there is no basis for choosing an answer.

4. One type of error a manager can make is to blame a worker for an

undesirable variation that is caused by the system. Refer to this as a type I error.
Another type of error a manager can make is to blame the system when a worker
caused the undesirable variation. Refer to this as a type II error. If a company changed
the basis for the upper and lower limits on a control chart from two standard
deviations to three standard deviations
    a. the number of type I errors would increase.
    b. the number of type II errors would increase.
    c. the number of both types of errors would increase.
    d. the number of both types of errors would decrease.
    e. there is no basis for choosing an answer.

5. Using the terminology associated with statistical process control (SPC), the
variation within a stable system is
    a. predictable within a range of values.
    b. controllable.
    c. in control.
    d. a and b.
    e. a and c.

6. Using the terminology associated with SPC, the variations resulting from common
causes are attributed to
    a. an out of control situation which should be investigated.
    b. an in control situation which should not be investigated.
    c. an out of control situation which should not be investigated.
    d. an in control situation which should be investigated.
    e. none of the above.

7. Using the terminology of statistical process control, a variation caused by the

system is
    a. common cause variation.
    b. assignable cause variation.
    c. special cause variation.
    d. a and b.
    e. b. and c.

8. Using the terminology of statistical process control, a variation that indicates that
the system may be out of control is
    a. common cause variation.
    b. assignable cause variation.
    c. special cause variation.
    d. a and b.
    e. b. and c.

9. Using the terminology of statistical process control (SPC), Type I errors are where
common cause variation is treated as assignable cause variation. Type II errors are
where assignable cause variation is treated as common cause variation. Which of the
situations below would minimize type II errors?
    a. Use SPC charts where the limits are based on 3 standard deviations.
    b. Use SPC charts where the limits are based on 2 standard deviations.
    c. Use SPC charts where the limits are based on 1 standard deviation.
    d. Use budget comparisons against actual results without using the concept of SPC.

10. Which of the situations below would minimize type I errors?

    a. Use SPC charts where the limits are based on 3 standard deviations.
    b. Use SPC charts where the limits are based on 2 standard deviations.
    c. Use SPC charts where the limits are based on 1 standard deviation.
    d. Use budget comparisons against actual results without using the concept of SPC.

11. Using the terminology of statistical process control (SPC), a stable system is
    a. efficient.
    b. predictable.
    c. in control.
    d. b and c.
    e. All of the above.

12. In general, finding and correcting an assignable cause variation

    a. represents an improvement in the system.
    b. returns the system from an unstable to a stable state.
    c. represents a type I error.
    d. a and b.
    e. b. and c.

13. Conceptually, control requires

    a. standards.
    b. a stable system.
    c. statistically established limits.
    d. a. and b.
    e. b. and c.

14. Statistically, an improvement in a system is defined as

    a. an improvement in the mean outcome. 
    b. a decrease in the system variability.
    c. a correction of an assignable cause.
    d. a and b. 
    e. all of the above.

15. When using the SPC methodology, a system is said to be stable when
    a. the system is efficient.
    b. the mean and range of variation caused by the system are controllable.
    c. the mean and range of variation caused by the system are predictable.
    d. the performance of the system is improving. 
    e. none of these.

16. When using a statistical control chart (SPC), a point outside the control limits is
attributed to
    a. common or random causes.
    b. assignable or special causes. 
    c. a problem caused by the system. 
    d. a and c. 
    e. b and c.

17. A predictable range of variation in the output of a particular worker occurs on a

routine basis. This variation represents
    a. common cause variation and is uncontrollable. 
    b. common cause variation and is controllable.
    c. assignable cause variation and is uncontrollable. 
    d. assignable cause variation and is controllable.
    e. none of these.

 18. Joiner and Gaudard use the term structural variation in discussing Deming’s
theory. This is
    a. common cause variation and uncontrollable. 
    b. common cause variation and controllable.
    c. assignable cause variation and uncontrollable. 
    d. assignable cause variation and controllable.
    e. none of these.

19. Deming used the red bead experiment to teach that

    a. most of the variation in a system is assignable cause variation.
    b. most of the variation in a system is common cause variation.
    c. the variation caused by the system is equally distributed across a group of
workers.
    d. a. and c.
    e. b. and c.

20. The red bead experiment was designed to show that

    a. workers tend to control their own performance.
    b. special or assignable causes account for most of the variation in performance.
    c. common or random causes account for most of the variation in performance.
    d. a balanced plant is not obtainable. 
    e. a and c.

      Professor David Garvin categorized quality into 5 different approaches: the
1 transcendent, the manufacturing-based, the user based, the product based and
. the value based. Making sure a product or service is "fit for its purpose" is which
kind of approach? 
Product based
  
Transcendent
  
Manufacturing-
  
based
User-based
  

2       The Operations view of Quality is "Quality is consistent conformance to customers'

. expectations". By this it is meant that: 
The product will be seen as synonymous with innate excellence
  
There are clear specifications consistently met which provide customers
  
with what they would realistically believe they should receive
Anything the customer wants and desires should be provided by the
  
organization
The product must be right every time irrespective of cost to the operation
  

3       Using Statistical Process Charts (SPC) on a process in control, what is the number
. of parts that will fall outside +/- 3 standard deviations of the mean? 
63 per million
  
45 per thousand
  
3 per thousand
  
0
  

4       The various definitions of quality do NOT include: 

. The transcendent approach
  
The minimum specification approach
  
The manufacturing-based approach
  
 The value-based approach
  

5       Quality control charts does not need to be investigated when: 

. Two consecutive points are near the control limits
  
Suspiciously 'average' behaviour occurs
  
Four consecutive points appear one side of the centre
  
line
An apparent trend occurs in one direction
  

     

If a sample of parts is measured and the average of the sample measurements is

6 in the middle of the tolerance limit, but some parts measure too low and other parts
. measure too high: 
The process is in control, with only natural causes of variation
  
The process is neither capable, nor in control
  
The process is in control, and no further action need be taken
  
The process is out of control
  
The process is in control but not capable of producing within the established
  
limits

7       Which of the following statements is correct? 

. Inspection is the most cost effective way of ensuring quality
  
Inspection provides the management information necessary to improve
  
processes
Inspection separates acceptable from unacceptable products
  
Inspection determines the root cause of product failures
  
Inspection always ensures that customers will be satisfied with goods and
  
services

8       Statistical Process Control is concerned with: 

. Determining the efficiency of an operations system
  
Measuring and controlling process variations
  
Inspecting goods before despatch
  
Measuring the amount of re-work required to rectify faulty goods
  
Identifying the security needs of an Operations system
  

9       Among the ‘Ten Determinants for Service Quality’ (Berry et al, 1985) are: 
. Specification and Security
  
Courtesy and
  
Comprehensiveness
Reliability and Responsiveness
  
Reliability and Reputation
  
Uniqueness and Universality