Quality Glossary Definition: Control chart Show
Also called: Shewhart chart, statistical process control chart The control chart is a graph used to study how a process changes over time. Data are plotted in time order. A control chart always has a central line for the average, an upper line for the upper control limit, and a lower line for the lower control limit. These lines are determined from historical data. By comparing current data to these lines, you can draw conclusions about whether the process variation is consistent (in control) or is unpredictable (out of control, affected by special causes of variation). This versatile data collection and analysis tool can be used by a variety of industries and is considered one of the seven basic quality tools. Control charts for variable data are used in pairs. The top chart monitors the average, or the centering of the distribution of data from the process. The bottom chart monitors the range, or the width of the distribution. If your data were shots in target practice, the average is where the shots are clustering, and the range is how tightly they are clustered. Control charts for attribute data are used singly.
Control Chart Example When to Use a Control Chart
Basic Procedure
Create a control chartSee a sample control chart and create your own with the control chart template (Excel). Control Chart ResourcesYou can also search articles, case studies, and publications for control chart resources. BooksThe Quality Toolbox Innovative Control Charting Improving Healthcare With Control Charts Case StudiesUsing Control Charts In A Healthcare Setting (PDF) This teaching case study features characters, hospitals, and healthcare data that are all fictional. Upon use of the case study in classrooms or organizations, readers should be able to create a control chart and interpret its results, and identify situations that would be appropriate for control chart analysis. Quality Quandaries: Interpretation Of Signals From Runs Rules In Shewhart Control Charts (Quality Engineering) The example of Douwe Egberts, a Dutch tea and coffee manufacturer/distributor, demonstrates how run rules and a Shewhart control chart can be used as an effective statistical process control tool. ArticlesSpatial Control Charts For The Mean (Journal of Quality Technology) The properties of this control chart for the means of a spatial process are explored with simulated data and the method is illustrated with an example using ultrasonic technology to obtain nondestructive measurements of bottle thickness. A Robust Standard Deviation Control Chart (Technometrics) Most robust estimators in the literature are robust against either diffuse disturbances or localized disturbances but not both. The authors propose an intuitive algorithm that is robust against both types of disturbance and has better overall performance than existing estimators. VideosControl Chart Excerpted from The Quality Toolbox, ASQ Quality Press. Which of the following statements best describes the business value of improved decision making?Which of the following statements best describes the business value of improved decision making? Improved decision making results in a large monetary value for the firm as numerous small daily decisions affecting efficiency, production, costs, and more add up to large annual values.
Which of the following is third stage in Simon's decision making model?First phase is intelligence activity which consists of finding occasion for decision making. Second phase is design activity which consists of identifying, developing and analysing all possible course of action. Third phase is choice activity which consists of choosing among courses of action.
Which types of decisions are more prevalent at lower organizational levels?In general, structured decisions are more prevalent at lower organizational levels, and unstructured decision making is more common at higher levels.
Which system is most likely used for day to day business operational decisions?Often used by upper and mid-level management, decision support systems are used to make actionable decisions, or produce multiple possible outcomes based on current and historical company data.
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