GMS401 CHAPTER 8: STATISTICAL PROCESS CONTROL EXAM
QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS
VERIFIED LATEST UPDATE
Statistical Process Control
the application of statistical techniques to control the processes.
Acceptance sampling
used to determine acceptance or rejection of material evaluated by a sample
Statistical Process Control is a process
used to monitor standards by taking measurements and corrective action as a product or service is being
used
Variability is inherent in every process
Natural or common causes
Special or assignable causes
Control Chart
is a graphical presentation of process data over time
Natural Variations
Also called common causes
Affect virtually all production processes
Expected amount of variation
, Output measures follow a probability distribution
For any distribution there is a measure of central tendency and dispersion
If the distribution of outputs falls within acceptable limits, the process is said to be "in control"
Assignable Variations
Also called special causes of variation
Generally this is some change in the process
Variations that can be traced to a specific reason
The objective is to discover when assignable causes are present
Eliminate the bad causes
Incorporate the good causes
Samples
To measure the process, we take samples and analyze the sample statistics following these steps
Distribution
There are many types of distributions, including the normal (bell-shaped) distribution, but distributions
do differ in terms of central tendency (mean), standard deviation or variance and shape
Natural Causes of Variation
if only natural causes of variation are present, the output of a process forms a distribution that is stable
over time and is predictable
Assignable Causes of Variation
if assignable causes of variation are present, the process output is not stable over time and is not
predictable
QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS
VERIFIED LATEST UPDATE
Statistical Process Control
the application of statistical techniques to control the processes.
Acceptance sampling
used to determine acceptance or rejection of material evaluated by a sample
Statistical Process Control is a process
used to monitor standards by taking measurements and corrective action as a product or service is being
used
Variability is inherent in every process
Natural or common causes
Special or assignable causes
Control Chart
is a graphical presentation of process data over time
Natural Variations
Also called common causes
Affect virtually all production processes
Expected amount of variation
, Output measures follow a probability distribution
For any distribution there is a measure of central tendency and dispersion
If the distribution of outputs falls within acceptable limits, the process is said to be "in control"
Assignable Variations
Also called special causes of variation
Generally this is some change in the process
Variations that can be traced to a specific reason
The objective is to discover when assignable causes are present
Eliminate the bad causes
Incorporate the good causes
Samples
To measure the process, we take samples and analyze the sample statistics following these steps
Distribution
There are many types of distributions, including the normal (bell-shaped) distribution, but distributions
do differ in terms of central tendency (mean), standard deviation or variance and shape
Natural Causes of Variation
if only natural causes of variation are present, the output of a process forms a distribution that is stable
over time and is predictable
Assignable Causes of Variation
if assignable causes of variation are present, the process output is not stable over time and is not
predictable
