Xbar/R control chart help (possibly a simple question)



Hi, I'm new to minitab and I'm having an issue. I am given a list of sample means which I compute in a minitab column. I am also given the corresponding sample ranges. There are 24 samples, each with n=5

So I go to "variable chart for subgroups", enter "5" for subgroup size, and this is where I have a problem: the chart has 5 points instead of 24, and I noticed that each point is a mean of 5 consecutive sample means. This is not what I want, I want a control chart for each sample mean.

I do not have this problem with attribute charts.


Forum Moderator
Staff member
Minitab expects the raw data (individual x's) to be entered instead of summary data (xbar's and R's). Minitab does have a macro available that will take summary data and create the chart.

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