I followed the instruction of a poster, which is

http://www.pokertracker.com/repository/statistics.php

Search for Standard deviation.

Download the statistic called: "Standard Deviation Per 100 Hands"

Now go to you're PT3.
Go to: Configure >>> Configure Stats >>> Statistics.
Press the "import" button and import the file you have downloaded.

Now you should have the Standard Deviation as a Stat in PT3!

and I updated the cache. But it didn't work. And I repeat the instructions.

Anyone knows what's happening? Will what I did have any negative affect on my database?

If you imported the statistic that way, it's there, you just need to add it to reports to see it. For whichever report you want to add it to, click the little wrench icon at the top right of the report and find the stat on the left and double click to add it to the report.

I'm not sure off the top of my head what stat section standard deviation was built in; it will only work in certain reports, but I'm not sure which.

Alternately, if you can wait a few days, standard deviation for your general play will be available in the next Beta version on a page that mimics the PTv2 More Details page.

thanks

Hey, I am also having the same problem with my standard deviation/100 always equaling 1..is there an update or something I can download? or should I just create a new formula myself like I had to do to calculate my rakeback?

We're still trying to figure out why this happens to some people and not to others - please report the problem so that we can investigate further - your extra information may be what we need to get this fixed.

Suggest thread is closed; latest version of PT3 includes st. dev. and other extra reports available

i just tried this and I get a wall of error code when using any of the pre loaded SD reports.
I also get 1.0 for SD when I add to the general tab.

The thread kraada linked you to explains how to best report your problem - please submit a support ticket and our support techs will investigate.

thank you, will do. It must not be a common issue.

Apparently, this has been a "known issue" since at least December 2009.

Is this particular feature unfixable, or is it just not important enough to be fixed?

I'm sure it can be fixed, but I don't know when it will be done.
Standard Deviation is working OK for me on the Sessions - Details report. If you're seeing the wrong value there try rebuilding the cache in Database > Housekeeping and see if that makes any difference.