Question 1

Referring to the SPC chart signals that a process is out of control,what type of problem does each signal indicate? List the signals.

Accepted Answer

The signals that something has changed a

Question 2

Common cause variation is variation in the output of a process that is unexpected and has an assignable cause.

Accepted Answer

A) True 
 B)False

Question 3

Special cause variation is variation in the output of a process that is naturally occurring and expected and that may be the result of random causes.

Accepted Answer

A) True 
 B)False

Question 4

The statistical process control (SPC)chart is one of the most important tools for identifying important issues to improve quality.

Accepted Answer

A) True 
 B)False

Question 5

The control limits in a control chart can be interpreted to mean:

Accepted Answer

A) any value falling outside the limits is a defect and the product should be discarded. 
B) the range of virtually all special cause variation. 
C) any value falling within the limits means the product is high quality. 
D) the range of virtually all common cause variation. 
A) any value falling outside the limits is a defect and the product should be discarded. 
B) the range of virtually all special cause variation. 
C) any value falling within the limits means the product is high quality. 
D) the range of virtually all common cause variation.

Question 6

The six most common sources of variation are people,machines,materials,methods,measurement,and environment.

Accepted Answer

A) True 
 B)False

Question 7

A company that fills soft drinks into bottles wishes to establish an   -chart to monitor the average fill level in the bottles.To do this,the company has taken a series of samples of size n = 4 bottles.The overall average fill is 12.03 ounces.The average range for the subgroups has been .06 ounces.Based on this information,what is the upper limit of the 3-sigma control limit?

Accepted Answer

A) .729 
B) .0437 
C) 12.09 
D) 12.074 
A) .729 
B) .0437 
C) 12.09 
D) 12.074

Question 8

In process improvement efforts,the goal is to first remove the common cause variation and then to reduce the special cause variation in a system.

Accepted Answer

A) True 
 B)False

Question 9

Each evening,a nationwide retail chain randomly calls 100 of the customers who came to their store that day to ask whether they were satisfied with the service they had received.The customers respond yes or no.Suppose the company has found over time that 8 percent of the customers are not satisfied ("no" answers),what is the 3-sigma upper and lower control limits for the appropriate control chart?

Accepted Answer

A) About .053 and .107 
B) 0 to about .16 
C) -.0.14 to about .16 
D) About -1.96 to 1.96 
A) About .053 and .107 
B) 0 to about .16 
C) -.0.14 to about .16 
D) About -1.96 to 1.96

Question 10

One of the most common sources of common cause variation is the people who are working in the process.

Accepted Answer

A) True 
 B)False

Question 11

A tire company is interested in monitoring the process that produced tread thickness on its tires.Every hour 4 tires are selected from production and the tread thickness is measured.Data for the past 25 days is shown as follows:   a.What type of control chart would you recommend be used in this case?
b.Compute the upper and lower control limits for these data.

Accepted Answer

a.The appropriate statistical process co

Question 12

A major airline is interested in monitoring customer satisfaction with its baggage handling process.To do so,each day the airline randomly selects 100 customers and surveys them to determine if they are satisfied or not with the service provided.After 20 samples,a total of 260 unsatisfied customers were surveyed.
a.If the airline wishes to use a control chart,which chart would you recommend and why?
b.Determine the 3-sigma control limits for the appropriate control chart.

Accepted Answer

a.The appropriate control chart in this

Question 13

Recently a shipping company took 30 samples,each of size n = 100,of packages that it was responsible for delivering.Out of the 3,000 total packages,300 were delivered late.In setting up an appropriate process control chart,what would be the correct 3-sigma upper control limit value?

Accepted Answer

A) 0.03 
B) 0.13 
C) 0.19 
D) 0.07 
A) 0.03 
B) 0.13 
C) 0.19 
D) 0.07

Question 14

A stable process is typically defined as one in which all output is operating within ± 3 standard deviations of the process center.

Accepted Answer

A) True 
 B)False

Question 15

Process control charts are used to provide signals to indicate when the output of a process is out of control.

Accepted Answer

A) True 
 B)False

Question 16

A process control chart can be used to determine whether the process average has shifted up or down,but is not useful for determining whether the process is just drifting in an upward or downward direction.

Accepted Answer

A) True 
 B)False

Question 17

Which of the following statements is correct?

Accepted Answer

A) A process can be in statistical control,yet it can be producing defects in abundance. 
B) At least three points outside the upper or lower control limits on a control chart are required before the process is deemed to be out of control. 
C) If a process is out of control,then the variation that is present is limited to common cause variation. 
D) When special cause variation is present,the process can be expected to be in control. 
A) A process can be in statistical control,yet it can be producing defects in abundance. 
B) At least three points outside the upper or lower control limits on a control chart are required before the process is deemed to be out of control. 
C) If a process is out of control,then the variation that is present is limited to common cause variation. 
D) When special cause variation is present,the process can be expected to be in control.

Question 18

Which of the following in not an out of control signal for an x-bar chart?

Accepted Answer

A) One or more points outside the control limits 
B) Seven or more consecutive points that all fall on the same side of the center line 
C) Six or more consecutive points moving in the same direction (an upward or downward trend) 
D) Fourteen points in a row,alternating up and down 
A) One or more points outside the control limits 
B) Seven or more consecutive points that all fall on the same side of the center line 
C) Six or more consecutive points moving in the same direction (an upward or downward trend) 
D) Fourteen points in a row,alternating up and down

Question 19

Which one of the following is not a source of variation?

Accepted Answer

A) People 
B) Measurement 
C) Materials 
D) Control 
A) People 
B) Measurement 
C) Materials 
D) Control

Question 20

Both p-charts and c-charts are designed for use when the data we are working with are referred to as attribute data.

Accepted Answer

A) True 
 B)False

Referring to the SPC chart signals that a process is out of control,what type of problem does each signal indicate? List the signals.

Common cause variation is variation in the output of a process that is unexpected and has an assignable cause.

Special cause variation is variation in the output of a process that is naturally occurring and expected and that may be the result of random causes.

The statistical process control (SPC)chart is one of the most important tools for identifying important issues to improve quality.

The control limits in a control chart can be interpreted to mean:

The six most common sources of variation are people,machines,materials,methods,measurement,and environment.

In process improvement efforts,the goal is to first remove the common cause variation and then to reduce the special cause variation in a system.

One of the most common sources of common cause variation is the people who are working in the process.

Recently a shipping company took 30 samples,each of size n = 100,of packages that it was responsible for delivering.Out of the 3,000 total packages,300 were delivered late.In setting up an appropriate process control chart,what would be the correct 3-sigma upper control limit value?

A stable process is typically defined as one in which all output is operating within ± 3 standard deviations of the process center.

Process control charts are used to provide signals to indicate when the output of a process is out of control.

A process control chart can be used to determine whether the process average has shifted up or down,but is not useful for determining whether the process is just drifting in an upward or downward direction.

Which of the following statements is correct?

Which of the following in not an out of control signal for an x-bar chart?

Which one of the following is not a source of variation?

Both p-charts and c-charts are designed for use when the data we are working with are referred to as attribute data.

The Where,Why,and How of Data Collection

Graphs,Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Filters

Exam 18: Introduction to Quality and Statistical Process Control

Referring to the SPC chart signals that a process is out of control,what type of problem does each signal indicate? List the signals.

Common cause variation is variation in the output of a process that is unexpected and has an assignable cause.

Special cause variation is variation in the output of a process that is naturally occurring and expected and that may be the result of random causes.

The statistical process control (SPC)chart is one of the most important tools for identifying important issues to improve quality.

The control limits in a control chart can be interpreted to mean:

The six most common sources of variation are people,machines,materials,methods,measurement,and environment.

In process improvement efforts,the goal is to first remove the common cause variation and then to reduce the special cause variation in a system.

One of the most common sources of common cause variation is the people who are working in the process.

Recently a shipping company took 30 samples,each of size n = 100,of packages that it was responsible for delivering.Out of the 3,000 total packages,300 were delivered late.In setting up an appropriate process control chart,what would be the correct 3-sigma upper control limit value?

A stable process is typically defined as one in which all output is operating within ± 3 standard deviations of the process center.

Process control charts are used to provide signals to indicate when the output of a process is out of control.

A process control chart can be used to determine whether the process average has shifted up or down,but is not useful for determining whether the process is just drifting in an upward or downward direction.

Which of the following statements is correct?

Which of the following in not an out of control signal for an x-bar chart?

Which one of the following is not a source of variation?

Both p-charts and c-charts are designed for use when the data we are working with are referred to as attribute data.

The Where,Why,and How of Data Collection

Graphs,Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Filters