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Topic: Zero Abundance incorrectly flagged

While producing a recent report we noticed that records with an abundance of "0 count" and any other abundance (for example "0 count of female; 3 count of male" are being marked as negative records.

The initial assumption was that this was due to the zero count going first, however on trying to re-order the abundances the zero was sorted back to the top, and i can find no other way to remove the flag without deleting the 0 count which is a legitimate part of the original record and we would like to retain.

I noticed this post: http://forums.nbn.org.uk/viewtopic.php?pid=1149#p1149 referring to flag issues in 2002 but our database has never used this version.

We are using version: 6.17.1.250

Natural History & Biodiversity Data Enthusiast

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Re: Zero Abundance incorrectly flagged

I have run some tests on this through the observation hierarchy and it looks like it is working Ok. If there is a zero abundance and also an abundance which is not zero then the indicator is not being set.  I am therefore not sure why you are having a problem. It could either be because at some time in the past the indicators were not being properly set. If this is the case then we can do a Batch Update to bring the indicators back in line. Alternatively, it could be because some combinations of measurements are not working as expected.

Mike Weideli

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Re: Zero Abundance incorrectly flagged

Hi Mike, Thanks for you're reply.

It seems following my earlier edit/save one of the records is now correctly marked, so i would have thought a batch update would work nicely and will certainly save me some time in tracking down the false flagging!

In regards to the measurements all the ones i have noticed so far have had a measurement of "Abundance" with a range of Qualifiers.

Natural History & Biodiversity Data Enthusiast

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Re: Zero Abundance incorrectly flagged

I have tested the setting of the zero abundance flag in the Taxon_Occurrence table as well, and can’t find any problems so I have written an xml report to list taxon occurrences with their zero abundance flag set to Yes but with measurement data that isn't zero – SRTOccsZeroAbundance.xml – see http://forums.nbn.org.uk/viewtopic.php?pid=14835#p14835 . Could you please run this and send me the results. I am hoping it will help identify what is going wrong and what needs to be done to fix it. It doesn’t handle cases where measurement data is text and the unit is Count but I am looking into that. If there aren’t too many you should be able to correct them manually as editing the abundance data will cause the zero abundance flag to be re-set.

Sally Rankin, JNCC Recorder Approved Expert
E-mail: s.rankin@btinternet.com
Telephone: 01491 578633
Mobile: 07941 207687

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Re: Zero Abundance incorrectly flagged

Sally, thanks for the XML report which is now working on text abundance. The report is only bringing back 91 instances of incorrect flagging, and it appears the actual number is only about half this (multiple determinations returning multiple instances) throughout the entire database.

I'll probably just go through each as this will give me a chance to full check the records, thanks again both to yourself and Mike!

Natural History & Biodiversity Data Enthusiast

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Re: Zero Abundance incorrectly flagged

I have now uploaded a version of my xml report that handles cases where measurement data is text. I had left out the single quotes in TOccD.Data != '0' which are needed because this is a text field. Note that if you run it from Reports – Run – SR Reports and enter * in the Survey box it lists all taxon occurrences with their zero abundance flag set to Yes but with measurement data that isn't zero not just those in a single survey or a selection of surveys.

Sally Rankin, JNCC Recorder Approved Expert
E-mail: s.rankin@btinternet.com
Telephone: 01491 578633
Mobile: 07941 207687