absence data and sampling protocols

discussion from DwC Hour #4: Evolution of Darwin Core Terms and Extensions...

Deb Paul - iDigBio: ooooh. Absence data!

David Shorthouse - CMN: Absence data with coordinates makes life as aggregator interesting.

Deb Paul - iDigBio: @David "we didn't see it - here :-)"

Teresa Mayfield (UTEP Biodiversity Collections): The absence data idea just blew me away...

Randy Singer (iDigBio-FLMNH): It could be in another database (e.g. occurrence database). The danger with "its not here data" could be that you just didn't see it/capture it though which is risky for research.

Elizabeth Martin (USGS): But the metadata should mention whether part of the protocol included looking for a specific species. You will then know it was not seen even though the species was looked for.

Randy Singer (iDigBio-FLMNH): true you just need to be careful about commission errors and giving false positives (the "positive" being not invasive here or something like that).

Deb Paul - iDigBio: Yes @Randy - effort matters - where did you look exactly, how did you look / sample - how long did you look. But very useful if you go back to same spot repeatedly and want to keep a record of what is / isn't noted visit to visit. Hard to do well. Some are doing it well. Check with Andrew Short at KU - if you'd like to see an example of how this is being done from an entomologist point of view.

John Wieczorek (Darwin Core): See Darwin Core terms samplingProtocol and samplingEffort.

Deb Paul - iDigBio: @Randy - see CReAC - Collection Resources for Aquatic Coleoptera - a database that incorporates absence data: https://sites.google.com/site/theshortlab/creac

tdwg / dwc-qa

absence data and sampling protocols #88