Deck 13: Supplement: Statistical Quality Control

Question 1

Data that are continuous such as weight and time are what type of data?

A) Variable data
B) Attribute data
C) Both variable and attribute data
D) Neither variable nor attribute data

Answer 1

A

Question 2

Which chart is used to track central tendency of sample means?

A) R
B) x-bar
C) p
D) c

Answer 2

B

Question 3

A reasonable sample size for samples collected for a control chart would be?

A) 1 to 2
B) 5 to 10
C) 25 to 50
D) 50 to 100

Answer 3

B

Question 4

A reasonable number of samples collected for a control chart would be?

A) 1
B) 5
C) 10
D) 25

Question 5

Humidity changes are likely to be an example of?

A) Assignable variation
B) Nonspecific variation
C) Specific variation
D) Natural variation

Question 6

The final step of Six Sigma and other quality improvement methods is?

A) Inspection
B) Statistical quality control
C) Variation elimination
D) Capability analysis

Question 7

If a sample point plots outside of the acceptable limits, we would say that the process is?

A) Out of statistical control
B) Capable
C) In statistical control
D) Not capable

Question 8

Which two charts are used together?

A) R and x-bar
B) p and c
C) p and R
D) x-bar and c

Question 9

Graphic representations of process performance over time are referred to as?

A) Control charts
B) Gantt charts
C) Pareto charts
D) Histograms

Question 10

If process performance measurements fall within the acceptable control limits and appear to be normally distributed around the center line, we would say that the process is?

A) Out of statistical control
B) Capable
C) In statistical control
D) Not capable

Question 11

SPC refers to?

A) Statistical process control
B) Statistical preference charting
C) Statistical process charting
D) Statistical preference control

Question 12

Statistical quality control was first considered by?

A) Rosen
B) Lam
C) Deming
D) Shewhart

Question 13

For an x-bar chart, x-double bar is defined as?

A) Sample range
B) Sample mean
C) Mean of sample means
D) Mean of sample ranges

Question 14

For an x-bar chart, x-bar is defined as?

A) Sample range
B) Sample mean
C) Mean of sample means
D) Mean of sample ranges

Question 15

Which chart is used to track sample ranges?

A) R
B) x-bar
C) p
D) c

Question 16

For an x-bar chart, R is defined as?

A) Sample range
B) Sample mean
C) Mean of sample means
D) Mean of sample ranges

Question 17

SQC refers to?

A) Statistical quality charting
B) Statistical quality capability
C) Statistical quality control
D) Statistical quality concept

Question 18

Random variation in a process is referred to as?

A) Assignable variation
B) Nonspecific variation
C) Specific variation
D) Natural variation

Question 19

Poor worker training is likely an example of what type of variation?

A) Assignable variation
B) Nonspecific variation
C) Specific variation
D) Natural variation

Question 20

Variation that is attributable to a cause that can be fixed is referred to as?

A) Assignable variation
B) Nonspecific variation
C) Specific variation
D) Natural variation

Question 21

The measure of the ability of a process to consistently produce a product or service within design specifications is referred to as?

A) Statistical quality control
B) Project management
C) Location factor rating
D) Process capability

Question 22

An x-bar chart in which all points are within the control limits is likely?

A) In control
B) Out of control
C) Both in control and out of control
D) Neither out of control nor in control

Question 23

A process with a Cpk value less than 1.0 implies?

A) The process is capable
B) The process is barely capable
C) The process is not capable
D) The Cpk value is unrelated to process capability

Question 24

A process with a Cpk value greater than 1.0 implies?

A) The process is capable
B) The process is barely capable
C) The process is not capable
D) The Cpk value is unrelated to process capability

Question 25

After initial control chart construction, the third step to continue statistical monitoring of a process is?

A) Collect samples of size four or five periodically
B) Plot sample means and ranges on the control charts
C) If the process trends out of control, investigate the causes and eliminate assignable variations
D) Ensuring that the process is in control before beginning statistical monitoring

Question 26

Which of the following refers to a customer's design requirements for a product or service?

A) Control limits
B) Test limits
C) Specification limits
D) Process limits

Question 27

Producer's risk can result in what type of error?

A) Type-I error
B) Type-II error
C) Type-III error
D) Type-0 error

Question 28

After initial control chart construction, the first step to continue statistical monitoring of a process is?

A) Collect samples of size four or five periodically
B) Plot sample means and ranges on the control charts
C) If the process trends out of control, investigate the causes and eliminate assignable variations
D) Ensuring that the process is in control before beginning statistical monitoring

Question 29

The A2 value for a sample size of 4 is?

A) 1.88
B) 1.023
C) 0.729
D) 0.577

Question 30

A process with a mean output of 14 and a standard deviation of output of 1 has been provided specification limits of 15 and 12. What is the Cpk value for this process?

A) 1.00
B) 0.67
C) 0.33
D) Not enough information to answer this question

Question 31

A process in which process variation fits well within the specification limits.

A) Process is easily capable
B) Process is comfortably capable
C) Process is just capable
D) Process is not capable

Question 32

After initial control chart construction, the second step to continue statistical monitoring of a process is?

A) Collect samples of size four or five periodically
B) Plot sample means and ranges on the control charts
C) If the process trends out of control, investigate the causes and eliminate assignable variations
D) Ensuring that the process is in control before beginning statistical monitoring

Question 33

When a shipment is received from suppliers and samples are taken and compared to a quality acceptance standard, this is referred to as?

A) Statistical quality control
B) Acceptance sampling
C) Process capability
D) Project management

Question 34

A process with a mean output of 16 and a standard deviation of output of 0.75 has been provided specification limits of 19 and 13. What is the Cpk value of this process?

A) 0.33
B) 1.33
C) 1.00
D) Not enough information to answer this question

Question 35

A process with a mean output of 14 and a standard deviation of output of 1 has been provided specification limits of 15 and 12. Which statement below is most appropriate for this process?

A) Process is not capable
B) Process is capable
C) Process is barely capable
D) Not enough information to answer this question

Question 36

A process in which process variation does not fit at all within the specification limits.

A) Process is easily capable
B) Process is comfortably capable
C) Process is just capable
D) Process is not capable

Question 37

A process with a mean output of 16 and a standard deviation of output of 0.75 has been provided specification limits of 19 and 13. Which statement below is most appropriate for this process?

A) Process is not capable
B) Process is capable
C) Process is barely capable
D) Not enough information to answer this question

Question 38

What type of control chart monitors the percent defective in a sample?

A) P
B) C
C) x-bar
D) R

Question 39

The upper control limit for an x-bar chart is given by?

A) D4*R-bar
B) D3*R-bar
C) x-double bar + A2*R-bar
D) x-double bar - A2*R-bar

Question 40

For an x-bar chart, R-bar is defined as?

A) Sample range
B) Sample mean
C) Mean of sample means
D) Mean of sample ranges

Question 41

Control ________ are used to monitor process performance.

Question 42

The level of defects a customer considers completely unacceptable is referred to as the?

A) PPTD
B) LTPD
C) AQL
D) PQL

Question 43

________ variation is due to causes that can be corrected or fixed.

Question 44

Broadly speaking, SPC and SQC are considered to be similar concepts.

Question 45

________ variation is due to random or uncontrollable causes.

Question 46

Process control refers to the measurement of the ability of a process to consistently produce a product or service within design specifications.

Question 47

What tool is used to illustrate the probability of accepting a shipment as a function of the shipment's quality?

A) Pareto chart
B) Process capability chart
C) Ishikawa diagram
D) Operating characteristic curve

Question 48

A machine in need of calibration would likely be a source of natural variation.

Question 49

Consumer's risk can result in what type of error?

A) Type-I error
B) Type-II error
C) Type-III error
D) Type-0 error

Question 50

A(n) __________ chart is used to monitor the central tendency of the sample means.

Question 51

When first constructing a control chart for a process, we require that the process itself be in control.

Question 52

The mean of variable data would be meaningful.

Question 53

The maximum level of defectives that a customer is potentially willing to accept is referred to as the?

A) PPTD
B) LTPD
C) AQL
D) PQL

Question 54

A negative lower control limt for a P chart should be truncated to zero.

Question 55

SQC techniques are used exclusively for processes that are out of control.

Question 56

The color of a product would be referred to as ________ data.

Question 57

The upper control limit for a P chart is calculated by p-bar + z*sigma-p.

Question 58

Acceptance sampling relies on the inspection of every unit in a shipment.

Question 59

Changes in weather would likely be a source of natural variation.

Question 60

Time is an example of attribute data.

Question 61

The sample standard deviation for a C chart is calculated by the formula _______.

Question 62

How does process capability analysis differ from the use of statistical process control charts?

Question 63

Why does a firm choose to implement a statistical quality control regime?

Question 64

A(n) _____ chart is used to monitor the percent defective in each sample.

Question 65

A(n) _____ chart is used to monitor the count of number of defects per unit of output.