Re: [compost_tea] Multiple tests from the same brew

From: <soilfoodweb_at_aol.com>
Date: Tue, 2 Sep 2003 06:52:39 EDT

We have data on repeated tests from the same tea brew taken at the same time,
and over time.

In general, variability with the assays we do have a 20% coefficient of
variation.

So, if the active bacterial reading you got was 20 ug, the variation would
mean the actual value could have been as high as 24 or as low as 16.

If the total bacteria was 1300 ug, then variation could have given values
between 1040 and 1560 ug. This gives you the ability to compare other samples
and figure out if they were significantly different or not.

If that confuses anyone, let me know and I'll try to find a different way to
express the concept.

OK? This is written up in a few of the publications on the methods - work by
Stamatidiatis, and the paper by Lodge. On my CV if anyone os interested.

Elaine
President, Soil Foodweb Inc.
www.soilfoodweb.com
SFI Oregon, USA
SFI Australia
SFI New York
SFI Europe
SFI New Zealand

"Hope is not a feeling. It is not the belief that things will turn out well,
but the conviction that what we are doing makes sense, no matter how things
turn out." -- Vaclav Havel, former President of the Czech Republic





Received on Tue Sep 02 2003 - 09:11:17 EDT

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