Lesson plan
Control chart
Control charts (also known as Shewhart charts, after Walter A. Shewhart, or process-behavior charts) are graphical plots used in statistical process control (SPC) to determine whether a manufacturing or business process is in a state of statistical control. They form the basis of modern statistical process control, and are one of the seven basic tools of quality control. A control chart plots a process statistic, such as a mean, range, or proportion, over time together with a centre line and upper and lower control limits that distinguish common-cause variation from special-cause variation. Points outside the control limits or non-random patterns within them indicate that the process should be investigated for assignable causes of variation. When a process is in statistical control, control charts can be used to predict its future performance. Control charts were invented by Shewhart at Bell Labs in the 1920s.
Article summary
Control charts (also known as Shewhart charts, after Walter A. Shewhart, or process-behavior charts) are graphical plots used in statistical process control (SPC) to determine whether a manufacturing or business process is in a state of statistical control. They form the basis of modern statistical process control, and are one of the seven basic tools of quality control. A control chart plots a process statistic, such as a mean, range, or proportion, over time together with a centre line and upper and lower control limits that distinguish common-cause variation from special-cause variation. Points outside the control limits or non-random patterns within them indicate that the process should be investigated for assignable causes of variation. When a process is in statistical control, control charts can be used to predict its future performance. Control charts were invented by Shewhart at Bell Labs in the 1920s.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.