As shown in this RDF <div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC.rdf">http://lod.taxonconcept.org/ses/ICmLC.rdf</a></div><div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC.rdf"></a>All the occurrences of this species will have this "type"</div>
<div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC#Occurrence">http://lod.taxonconcept.org/ses/ICmLC#Occurrence</a></div><div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC#Occurrence"></a>All the individuals of this species will have this "type"</div>
<div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC#Individual">http://lod.taxonconcept.org/ses/ICmLC#Individual</a></div><div><br></div><div><a href="http://lod.taxonconcept.org/ses/ICmLC#Individual"></a>Which then makes it easy to query for all occurrence or all individuals of this species concept.</div>
<div><br></div><div>The exact predicate is different but when you tie a subject to and object you are essentially making the subject a "type" of the object.</div><div><br></div><div>Which is why you can see the occurrences for that species in the triplestore, when you ask it to describe that type.</div>
<div><br></div><div>< <a href="http://lsd.taxonconcept.org/describe/?url=http%3A%2F%2Flod.taxonconcept.org%2Fses%2FICmLC%23Occurrence&sid=16&urilookup=1">http://lsd.taxonconcept.org/describe/?url=http%3A%2F%2Flod.taxonconcept.org%2Fses%2FICmLC%23Occurrence&sid=16&urilookup=1</a> ><br>
</div><div><br></div><div>- Pete<br><br><div class="gmail_quote">On Tue, Oct 26, 2010 at 9:46 PM, Hilmar Lapp <span dir="ltr"><<a href="mailto:hlapp@nescent.org">hlapp@nescent.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im"><br>
On Oct 25, 2010, at 4:37 AM, Cam Webb wrote:<br>
<br>
> But then what exactly are the Occurrences themselves? From Richard<br>
> Pyle:<br>
><br>
> ``So, an Occurrence is the intersection of an Individual and an<br>
> Event.<br>
> An Event is a Location+Time[+other metadata]. Each Event may have<br>
> multiple Occurrences (i.e., one for each distinct Individual at<br>
> the same<br>
> Location+Time). Also, an Individual may have multiple Occurrences<br>
> (one<br>
> for each Event at which the same Individual was documented).''<br>
><br>
> So the Occurrence is the Individual _itself_ bounded by space and<br>
> time,<br>
<br>
<br>
</div>While for the purposes of exchanging occurrence data in a commonly<br>
agreed upon markup, i.e., Darwin Core, this may be perfectly<br>
acceptable, I think there are some serious issues in the above when we<br>
try to tighten up the semantics so that machines could do something<br>
with them, or so they can seamlessly integrate into the semantic web.<br>
<br>
First there is an internal inconsistency: on the one hand occurrences<br>
*are* individuals (albeit only a subset - though see below), and on<br>
the other hand individuals *have* occurrences.<br>
<br>
Second, occurrence is said to be the intersection of an individual and<br>
an event, or an individual and space and time. In the semantic web,<br>
OWL models deal with sets of individuals. I would argue that the<br>
intersection set of an individual organism (or a set of individual<br>
organisms) and an event (or a set of events) is empty, because there<br>
are no events that are also individual organisms, and vice versa.<br>
<br>
Alternatively, and using "Individuals" as short hand for "instances of<br>
an organism" we could say that an Occurrence is the intersection of<br>
all Individuals belonging to a specific taxon, all Individuals at a<br>
specific location, and all Individuals existing at a specific time.<br>
Then an instance of an Occurrence would be an Individual in that<br>
intersection, and taxon, location, and time would be (among) its<br>
properties.<br>
<br>
Just some thoughts.<br>
<br>
-hilmar<br>
<font color="#888888">--<br>
===========================================================<br>
: Hilmar Lapp -:- Durham, NC -:- <a href="http://informatics.nescent.org" target="_blank">informatics.nescent.org</a> :<br>
===========================================================<br>
</font><div><div></div><div class="h5"><br>
<br>
<br>
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</div></div></blockquote></div><br><br clear="all"><br>-- <br>---------------------------------------------------------------<br>Pete DeVries<br>Department of Entomology<br>University of Wisconsin - Madison<br>445 Russell Laboratories<br>
1630 Linden Drive<br>Madison, WI 53706<br><a href="http://www.taxonconcept.org/" target="_blank">TaxonConcept Knowledge Base</a> / <a href="http://lod.geospecies.org/" target="_blank">GeoSpecies Knowledge Base</a><br><a href="http://about.geospecies.org/" target="_blank">About the GeoSpecies Knowledge Base</a><br>
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