Pete,
I was going to ask questions about this the first time you mentioned it, but got distracted.  I guess the main question I have is: what you would "do" with it?  I guess it could be considered an identifier for a spot on the earth, but based on what I've read about guids it's considered to be a "no-no" to try to infer stuff about a resource by looking at the form of the identifier.  Rather one should look at the metadata associated with the identifier to understand things about the identifier (which you provide with geo:lat and geo:long).  I suppose that one could consider this to be some kind of identifier that could be reused, but particularly since the precision of your lat and long are 8 digits, it is highly unlikely that anybody besides you is ever going to choose to use this identifier over (vs. 44.86,-87.23 which would be imprecise enough to include a lot of places to which people might want to refer).  I may just be misunderstanding the purpose you intend.

The other question is a more general one.  Do we need more ways to specify uncertainty in location than we already have?  We already have dwc:coordinateUncertaintyInMeters and dwc:coordinatePrecision .  I've been using dwc:coordinateUncertaintyInMeters with a seat-of-the pants estimate on my part about how accurate I think my geolocation is (expressed in meters).  That may be a misuse of this term because I'm really thinking radius around a point rather than uncertainty of coordinates.  But as a practical matter, if I think my estimate of location is good to 1000 m (vs. 100 m or 10000 m) does it really matter if I'm talking about a square or a circle?  In any case, I'm saying, this lat/long could be off from the actual location by a km.  If I had a GPS receiver that allowed me to download the actual estimated accuracy (based on satellite signals and whatever else), then I would populate dwc:coordinateUncertaintyInMeters with that, but mine crummy old one doesn't.  To me the most important thing is for users to know whether this is a ballpark estimate or if they could expect to actually be able to walk up to the tree using the coordinates they give.

Steve

Peter DeVries wrote:
I wrote about this earlier but I never heard anything back.

I have made something that uses the geo vocabulary but also allows pointRadiusSpatial fit measure that I call radius.

The advantage is that this adds a standard way to deal use something like an extent or pointRadiusSpatial while still benefiting from the widely used geo vocabulary.

It also allows these "Areas" to be referenced in a commonly understood urn way that using a ietf standard.

For example: "geo:44.86528100,-87.23147800;u=10"

There are still some things I need to fix and check with this vocabulary but I am wondering if there is any interest in incorporating this into the DarwinCore.

If not I will probably change the name of the ontology.

There are also things in the example below that are not part of my proposal.

I have what I call "Areas" that look like this:

  <dwc_area:Area rdf:about="geo:44.86528100,-87.23147800;u=10">
    <dcterms:title>44.86528100, -87.23147800 Radius 10 meters</dcterms:title>
    <dcterms:isPartOf rdf:resource="http://lod.taxonconcept.org/ontology/void#this"/>
    <dcterms:identifier>geo:44.86528100,-87.23147800;u=10</dcterms:identifier>
    <dcterms:created>2010-10-28T00:00:00-0500</dcterms:created>
    <dcterms:modified>2010-11-09T16:33:34-0600</dcterms:modified>
    <geo:lat>44.86528100</geo:lat>
    <geo:long>-87.23147800</geo:long>
    <dwc_area:radius>10</dwc_area:radius>
    <txn:elevation>186.54</txn:elevation>
    <txn:continent>North America</txn:continent>
    <txn:countryCode>US</txn:countryCode>
    <txn:country>United States</txn:country>
    <txn:stateProvince>Wisconsin</txn:stateProvince>
    <txn:county>Door</txn:county>
    <txn:localityText>Town of Sevastopol</txn:localityText>
    <txn:locationName>Shivering Sands Natural Area Woods</txn:locationName>
    <txn:areaHasOccurrence rdf:resource="http://ocs.taxonconcept.org/ocs/f522444a-2dd9-400e-be59-47213ef38cb9#Occurrence"/>
    <txn:areaHasObservedSpeciesConcept rdf:resource="http://lod.taxonconcept.org/ses/ICmLC#Species"/>
    <txn:areaHasIndividual rdf:resource="http://ocs.taxonconcept.org/ocs/f522444a-2dd9-400e-be59-47213ef38cb9#Individual"/>
    <txn:areaInStateProvince rdf:resource="http://sws.geonames.org/5279468/"/>
    <txn:areaInCounty rdf:resource="http://sws.geonames.org/5250768/"/>
    <wdrs:describedBy rdf:resource="http://ocs.taxonconcept.org/ocs/f522444a-2dd9-400e-be59-47213ef38cb9.rdf"/>
  </dwc_area:Area>

I recently added the following predicates, but have not altered my RDF examples.

#featureContainsArea
#areaWithInFeature

http://lod.taxonconcept.org/ontology/dwc_area.owl

OWL Doc http://lod.taxonconcept.org/ontology/dwc_area_doc/index.html

The predicates are a bit awkward, but I wanted to be clear that this was to link an "Area" like "geo:44.86528100,-87.23147800;u=10" to a Geonames "Feature".

I thought a different set of predicates could be created to deal with some other class of "SpatialThing" if needed.

Respectfully,

- Pete

---------------------------------------------------------------
Pete DeVries
Department of Entomology
University of Wisconsin - Madison
445 Russell Laboratories
1630 Linden Drive
Madison, WI 53706
TaxonConcept Knowledge Base / GeoSpecies Knowledge Base
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