Variation & Control Flashcards
What is the responsibility of management when it comes to variation?
All processes have variation. A portion of management’s responsibility is to control that variation to be within acceptable levels.
When do you use statistical process control?
All process have variation, so an analysis to understand and control variation is always appropriate.
A management goal in the 21rst century?
Process variation exists in all processes. A management goal of many 21st business managers is to identify the sources of variation and control the levels of variation within a process. Variation leads to unpredictable performance.
Walter Shewhart
SPC was formulated by Walter Shewhart in the 1920s. He explained the concept of special cause variation and common cause variation. This led to the creation of control charts for monitoring process performance to determine the presence and magnitude of each. In addition, he created the process capability indices to show whether the process could meet the customer’s expectations.
Shewart demonstrated his theories in Department of Defense arsenals and then with Defense contractors during World War II. The widespread adoption and success of SPC during this time turned it into a standard business management process for manufacturing operations.
Edward Deming
SPC was further developed by one of Shewhart’s students, Edward Deming. Deming used SPC in the USA Department of Agriculture during the 1930s where he found the need to add the sampling theories and principles to SPC. He worked with Shewhart in the Defense industry during World War II. However, Deming is best known for his work after the war.
If variation always exist, what is your goal?
identify it, understand it, and control it
Can SPC be applied to all businesses?
SPC can be applied to any business process, and often has a larger impact on administrative and support processes since they seldom have established quality control procedures.
Variation exists in all business processes?
True
Edward Deming was the creator of statistical process control charts.
False
The first wide-spread use of statistical process control was by the US defense industry during WWI.
False
Edward Deming expanded the principles of statistical control into a management discipline he called the System of Profound Knowledge.
True
Variation represents uncertainty and can lead to defects and losses for both the business and its customers.
True
Walter Shewhart first clarified the difference between special cause and common cause variation.
True
Edward Deming believed that management was the source of approximately 20% of process variation.
False
Statistical Process Control (SPC) is a recognized methodology for identifying and controlling variation.
True
