Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [control-chart]

One of the key tools of process control.

The purpose of a control chart is to characterize how well a process is staying within stable and targeted behavior and alert in a timely manner when it has departed from it.

NIST link on process control tools: http://www.itl.nist.gov/div898/handbook/pmc/section1/pmc12.htm

The NIST pages on Control Charts are here: http://www.itl.nist.gov/div898/handbook/mpc/section2/mpc221.htm

Here is a text on the subject: http://people.irisa.fr/Michele.Basseville/kniga/

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Understanding statistical control charts

Control charts are all the rage at my company these days. Our "data analysts" (quotes are on purpose) are putting control limits on almost all graphs that they produce. The other day we were looking at some graphs of calls into our support call…
Dave Kincaid
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How to interpret a control chart containing a majority of zero values? (Part 2)

(I know it is not quite appropriate to quote it as "part 2", but since the question has been dormant for quite a while, I hope by doing this will rise peoples' attention again, you may have a look of part I here.) I have come across an article…
lokheart
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Using control charts for data with non-constant mean?

My company would like to use control charts (Shewhart, EWMA, or both) to detect changes to the distributions of our key business metrics. For instance, we could sample user signups each day and determine whether a change to our sales webpage has…
Travis
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Using geometric mean / geometric standard deviation in statistical process control chart

I am trying to control a binomial proportion that hovers pretty close around 0.1% - 1.0%. Since it seems like dropping from 0.1% to 0.05% is equally as severe as increasing to 0.2% (halving the occurrences, doubling the occurrences), it makes sense…
Tim Harper
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How to get the improvement index in monthly basis for employees absence

I have the following information for each month of the year: Total Absence Days in a given month Total Headcount in a given month I want to get an index in which I can compare months and see if things are improving or not. If I only use the number…
Abu
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