[seek-kr-sms] OBOE discussion: current version

[Joshua Madin]

Hi Sergey.  These are great comments -- I'll infuse my comments  
below.  We still don't have good answers for all of them.

> 1.      Observable is either Entity or Characteristic (at the  
> moment).  Characteristic has only one subclass Dimension, which  
> defines the set of base quantities such as length, weight, etc. ,  
> Dimension includes only things measured in quantities. Thus at the  
> moment we are missing specification for observations of such  
> characteristics as color, smell, taste or anything which is  
> measured in qualitative scale.
This is a question that has come up a lot recently and really needs  
to be confronted with some good examples.  The idea was that nominal  
measurements would just be given unit "name" and a characteristic,  
such as "red".  This would mean having these characteristics in an  
extension ontology such as a "classifiation ontology" (which would  
plug into OBOE's charactersitic).

Ordinal measurements may not be as easy to deal with.  It might work  
in the same way as above, but use the unit "rank".  However, the  
ordinal ontology would need to contain constructs that deal with  
"direction" or "magnitude".  For example, "high" is distinct from and  
of greater magnitude than "low".  This ontology would have to be able  
to deal with arbitrary numbers of levels, similar to the way we dealt  
with Observation in OBOE for coping with experimental design.  The  
idea was to remove these kind of things (i.e., characteristics) from  
the core ontology because the way that people want to use them are so  
variable.
> 2.      Continuing the same subject. If we observe say color of a  
> lion , is that a measurement or just an observation? If we qualify  
> such recording of color as measurement, then given the specific  
> association of  measurement with units, we must have units for all  
> qualitative scales. Having one unit “qualitative” will be of no  
> use, because this would lump  together unrelated thing such as  
> colors {read, orange….} , health level {exellent, good,…}, etc.  
> Therefore, I would vote not to call such things as recording of  
> color measurement, but consider them as special kind of observation
The color of a lion is a measurement with unit "Name" and  
characteristic, e.g., "Blue", where blue is selected from an  
extension ontology.  This is the way we have it now as far as I  
understand it.  The overarching point is that we are trying very hard  
to separate Observation and Measurement for many reasons, such as  
context operating only on Observations.  This gives us some powerful  
ways to deal with ecological data, such as interpreting experimental  
design.  Therefore, I think that it is better to call things such as  
color measurements; e.g., color of stick; length of stick.  I'd be  
interested to see examples of how color could be defined/described as  
a special kind of observation.
> 3.      Each specific dimension has a set of related units. Say,  
> length may be measured in meters, centimeters , microns . I believe  
> that this  association of a specific dimension with a set of  
> respective units is an important intuition that helps to make sense  
> of calculations. Why do not we draw an additional property hasUnit  
> with domain Dimension  and range  Unit
Hmm.  This sounds like a good idea.  I'll think about this some more.
> 4.      O&M scheme for Observation and Measurement has additional  
> notion of observation/measurement procedure. It looks as if this  
> concept could be easily added to OBOE by attaching property  
> hasProcedure either to observation or to Measurement or to both. If  
> we have property has procedure with domain that include both  
> Observation and Measurement, then we might need to think how  
> measurement procedure is related to observation procedure. Does it  
> have sense to have both observation procedure and measurement  
> procedure?
Yes.  This would certainly make OBOE more complete, and I agree that  
this property should operate at both the Observation and Measurement  
level.  For example, we used a telescope for observing, but a tape  
measure for measuring.  It seems that EML already captures much of  
the procedural stuff, so we need to discuss if we want to become more  
redundant (e.g., EML covers much of the unit stuff as well), or  
whether we just want to fill in the gaps that EML can't cope with.   
Personally, I think that OBOE should be a stand-alone initiative, and  
therefore include the concept of observation and measurement procedure.
> 5.      There is property hasMeasuredCharacteristic with domain  
> Observation and range Measurement. Is Measurement an event,  
> procedure or characteristics of something? I think that Measurement  
> as such is not a characteristic but an event. But measurement is a  
> measurement  *of* a characteristic. Therefore property  
> hasMeasuredCharacteristi should have domain Measurement and the  
> range Characteristic. (but in this case it will duplicate property  
> hasSubject) . In fact the choice of range Characteristic is  
> determined by the name of the property hasMeasuredCharacteristic.  
> The domain may be either Measurement or Observation.
I totally agree and there has been some discussion about this.  I  
really like your use of the word "event", I think this makes what we  
are actually doing much clearer.  For example, we Observe a tree,  
each Measurement is an event relating to that Observation, and a  
Measurement is of some characteristic.  I second the move changing  
the property between Observation and Meaurement to something like  
"hasMeasurementEvent".

Cheers,
Josh
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