[tdwg-content] Treatise on Occurrence, tokens, and basisOfRecord [SEC=UNCLASSIFIED]

Richard Pyle deepreef at bishopmuseum.org
Thu Oct 28 21:12:11 CEST 2010

I agree with most of the statements made during this thread (the majority of
which were posted prior to sunrise in Hawaii).

> > I thought that was the reason others had introduced "event" 
> as place +
> > time.   Otherwise, what is the reason for "event"?
> I was wondering the same thing. Event=(Location, Time) 
> strikes me as weird, for a couple of reasons:
> i. Intuitively, an event is something that happens at a 
> region of space/time, not the region itself.
> ii. More significantly, a DwC:event is a container for 
> metadata that gets attached to occurrences via eventID. A 
> DwC:event corresponds to the intuitive definition above, 
> since you can have multiple DwC:events over the same 
> space/time region, e.g. two groups surveying for different 
> taxa, using different methodologies.

A couple of things:

1) In my mind, an Event is, and has always been, in its most fundamental
form, a "tuple" (exercising my new vocabulary) of Location + Time, both of
which are scoped in some way.

2) Less clear is whether an "Event" also includes things like collectors,
collection method, habitat description, etc. (deliberately avoiding dwc
terms at the moment).

3) Coming back to point 1, an Event does not necessarily need to be treated
as a tuple of Location + Time, if you vew it from the perspective of
4-dimensional space-time (with time representing the 4th dimension, in
addtion to the more conventional 3 dimensions of space).  Location is
already a tuple of latitude and longitude; and indeed is most properly
represented as a triple of latitude+longitude+altitude (X+Y+Z). Time is
simply the fouth dimension. In other words, there is a fundamental argument
that could be made that really Location+Time boils down to a single
coordinate in 4-dimensional space-time.

Side Note to Jim Croft:  We're still only treading on the outskirts of
weirdness -- we still have a lot of weirdness-space that we have yet to
venture into.


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