What is SPC? How to calculate X Bar and R Bar char?

Question

Accepted Answer

SPC stands for Statistical Process Control. X Bar and R Bar charts are used to monitor the stability of a process over time.

SPC is a method of quality control which uses statistical tools to monitor and control a process.
X Bar chart is used to monitor the central tendency of a process by plotting the average of a sample over time.
R Bar chart is used to monitor the variability of a process by plotting the range of a sample over time.
To calculate X Bar, you sum up all the sample values and divide by the number of samples.
To calculate R Bar, you find the range of each sample and then calculate the average range.

Accepted Answer

SPC( Statistical process Control) The X- bar chart shows how the mean or average changes over time and the, R chart shows how the range of the sub groups changes over time. It is also used to monitor the effects of process improvement theories.

What is SPC? How to calculate X Bar and R Bar char?

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