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Simulating data with random() formula

agneshb

Community Trekker

Joined:

Jan 19, 2014

Hi,

If I have a column of data (A) and want to simulate a test result on that column (from a normal distribution(SD of 10 and mean = the number in column A), can someone confirm it is right to do it with the following formula:

Random norma()*10+A

If it's not, how can I do it?

also, is there a way to enter the SD a RSD(%)??

Thanks!

Agnès

1 ACCEPTED SOLUTION

Accepted Solutions
stan_koprowski

Community Manager

Joined:

Aug 8, 2012

Solution

Hello,

You are on the right track.  The Random Normal function by default will use mu =0 and sigma = 1.

This can easily be changed in your formula as shown below:

7415_Screen Shot 2014-10-10 at 10.01.51 AM.png

The Coefficient of Variation is what you need to display the RSD or %RSD.  To display the coefficient of variation look under the red triangle of Summary Statistics and select Customize Summary Statistics. 

7418_Screen Shot 2014-10-10 at 10.25.42 AM.png

Check the box next to CV and then click OK. 


7419_Screen Shot 2014-10-10 at 10.27.04 AM.png

And if you look at the distribution of both A and the simulated A we do indeed now have an normal distribution for the simulated A.

7417_Screen Shot 2014-10-10 at 10.19.24 AM.png

Best,

Stan

3 REPLIES
stan_koprowski

Community Manager

Joined:

Aug 8, 2012

Solution

Hello,

You are on the right track.  The Random Normal function by default will use mu =0 and sigma = 1.

This can easily be changed in your formula as shown below:

7415_Screen Shot 2014-10-10 at 10.01.51 AM.png

The Coefficient of Variation is what you need to display the RSD or %RSD.  To display the coefficient of variation look under the red triangle of Summary Statistics and select Customize Summary Statistics. 

7418_Screen Shot 2014-10-10 at 10.25.42 AM.png

Check the box next to CV and then click OK. 


7419_Screen Shot 2014-10-10 at 10.27.04 AM.png

And if you look at the distribution of both A and the simulated A we do indeed now have an normal distribution for the simulated A.

7417_Screen Shot 2014-10-10 at 10.19.24 AM.png

Best,

Stan

agneshb

Community Trekker

Joined:

Jan 19, 2014

Thanks Stan!

michael_jmp

Staff

Joined:

Jun 23, 2011

If you find yourself going to the Customize Summary Statistics options every time you run the Distribution platform, you might be interested in knowing that you can use Platform Preferences to set the summary statistics that show up.

See Re: how to change default summary statistics displayed in distributions.

Michael Crotty
Sr Statistical Writer
JMP Development