How to calculate mean minus 3 sigma?

[#1]

Is there a way to program Jmp 8.0 to calculate mean - 3 standard deviations from a set of data? I use this criteria in my tests and until now have always had to do it in Excel. The problem with that is that I have to validate the spreadsheet I write to do the calculation. Using Jmp, I don't think I'd have to

Thanks,
Greg

[#2 · Accepted solution]

I would use the control chart platform to generate the mean +/- 3 sigma represented by the UCL and LCL. If you are trying to do it in the JMP table then try using the tabulate platform and drag and drop the statistics of interest. Then make a table and add columns using the formula editor to generate your calculation of interest.

[#3]

This script will make a new formula column for each selected column in your data table. The formula will be the mean of the column minus 3s.

initdata = Current Data Table();
sc = initdata << Get Selected Columns();
scn = initdata << Selected Column Names();
for(i=1,i<=length(sc),i++,
values = sc[ i ] << Get as Matrix;
m = mean(values);
s = stddev(values);
tmp = "initdata << New Column(\!"Mean of " || Char(sc[ i ]) || " - 3s\!", Formula(" || Char(m) || " - 3*" || Char(s) || "));";
Eval(Parse(tmp));
);

Message was edited by: mewing