[Crm-sig] NEW ISSUE: Approximate Dimensions

Martin Doerr martin at ics.forth.gr
Wed Oct 16 21:18:07 EEST 2019


Hi Robert,

I have been a bit sloppy, as always;-).

A phenomenal place is thought to be recognizable within some fuzzy 
limits. So, indeed, all spatial coordinates for a phenomenal place are 
approximations. For those approximations, we normally use the properties 
"has former or current location" or "falls within", which both include 
the true place. That means, that the intersection of all those is still 
includes the true place. With these properties, I can query absolutely 
where the place is guaranteed not to be, and within which limits I find 
it. With P189, we mean an approximation of unknown guaranteed relations 
to the approximated. So, we cannot query yes or no where the real place 
is in relation to the approximation.

The same reasoning holds for many dimensions, but there is no typical 
practice as vague as that of providing a point near a place.

On the other side, many dimensions are not stable over time. For those, 
each measurement provides another dimension. Many measurements are given 
with statistical deviation values. The scenario intersecting all 
measurements to get closer to the real value normally does not hold. It 
will be a combination of measurement deviations and varying "real 
value", and intrinsic fuzziness of the property measured.

Therefore I suggest to regard any dimension as an approximation, except 
for counting stable aggregates of things.

Would that make sense:-)?

Best,

Martin

On 10/16/2019 6:54 PM, Robert Sanderson wrote:
>
> Thanks Martin!  A couple of clarifying questions, please …
>
> > The point is, that true numerical values of Dimensions do not exist 
> for continuous value spaces.
>
> Could you explain how you see this being different for E53 Place? The 
> true Place also doesn’t exist as space is also continuous. Doubly so 
> as the definition of place says it is independent of matter. No matter 
> how precise I am about a lat/long/altitude, I still could be more 
> precise. Or more precise about a location relative to an object as a 
> frame of reference; notably as this frame of reference would need to 
> be measured … which would mean that Place would rely on the 
> Dimensions. So it seems like we can reduce the Place approximation to 
> a Dimension approximation, at least in the case of relative coordinate 
> spaces.
>
> > For any approximation with known inclusion or overlap properties to 
> the real place, P189 should NOT be used. A "real place" can be 
> confirmed by multiple observations for things that do not move or have 
> not moved.
>
> And also for this … how would we have multiple observations of the 
> Place, such that it was clear that they were all approximations of a 
> single phenomenal place, without using P189?  For example, I have a 
> bounding box for my city of birth, and a centroid pin for it … I 
> wasn’t born in two places, yet without using P189, I would need to 
> have two P7s … no? What am I missing? 😊
>
> Many thanks,
>
> Rob
>
> *From: *Crm-sig <crm-sig-bounces at ics.forth.gr> on behalf of Martin 
> Doerr <martin at ics.forth.gr>
> *Date: *Wednesday, October 16, 2019 at 8:18 AM
> *To: *"crm-sig at ics.forth.gr" <crm-sig at ics.forth.gr>
> *Subject: *Re: [Crm-sig] NEW ISSUE: Approximate Dimensions
>
> Dear Robert, All,
>
> Your proposal well taken, but the recent change in the scope note was 
> exactly that "The properties of the class E54 Dimension allow for 
> expressing the numerical approximation of the values of instances of 
> E54 Dimension. ".
>
> The point is, that true numerical values of Dimensions do not exist 
> for continuous value spaces. Therefore, any measurement and opinion 
> about the values are approximations.So, there is no need for another 
> property. Measurements have typically known tolerances, which may be 
> statistical, as mean deviations, or absolute.
>
> The property P189 was introduced because of the huge number of 
> geo-referenced resource with no indication how distant or different 
> the approximating area is from the real place. For any approximation 
> with known inclusion or overlap properties to the real place, P189 
> should NOT be used. A "real place" can be confirmed by multiple 
> observations for things that do not move or have not moved.
>
> This scenario does not exist in the same way for dimensions *in general.*
>
> I recommend to adjust scope notes and guidelines adequately. If a 
> dimension is given as 10cm, it is per definitionem an approximation, 
> because no natural thing has dimension 
> 10,00000000000000000000000000000000000000000000000000000000000000000000000 
> cm.
>
> A fine example of measurement tolerances is the recent problem of 
> determining the proton radius:
>
> https://en.wikipedia.org/wiki/Proton_radius_puzzle
>
> See also:
>
> http://pdg.lbl.gov/2012/reviews/rpp2012-rev-history-plots.pdf
>
> https://www.quantamagazine.org/proton-radius-puzzle-deepens-with-new-measurement-20160811/
>
> I think it is a question of guide lines how to interpret the absence 
> of P10a,b.
>
> Opinions?
>
> Best,
>
> Martin
>
> On 10/15/2019 7:13 PM, Robert Sanderson wrote:
>
>     Dear all,
>
>     In recent history, we have added P189 approximates for the
>     practically ubiquitous scenario where we have recorded the
>     approximate “declarative” place of an event, but not the exact
>     “phenomenal” place. P189 allows us to say that the event took
>     place at the phenomenal place, which is then approximated by the
>     declarative place.
>
>     Thus:
>
>       Birth_of_Rob a E67_Birth ;
>
>     p7_took_place_at [
>
>             a E53_Place ;
>
>     rdfs:label “The exact place Rob was born” ;
>
>     p189i_approximated_by [
>
>     a E53_Place ;
>
>     rdfs:label “New Zealand” ;
>
>      // …
>
>             ]
>
>         ]
>
>     This gives us two significant advantages:
>
>      1. We can have multiple declarative places associated with the
>         single phenomenal place. This allows us to be clear that the
>         event took place in one location, but we have multiple ways to
>         describe that location in our information system.
>      2. If we can be precise (enough) about the phenomenal place (e.g.
>         we have the GPS coordinates from the digital camera that took
>         the photograph), then we do not have a different model … we
>         can simply ascribe those coordinate values to the phenomenal
>         place.
>
>     While the E53 Place scope notes do not talk about approximation,
>     there is another class that does … the very next one, E54 Dimension.
>
>     An instance of E54 Dimension represents the true quantity,
>     independent from its numerical
>
>     approximation, e.g. in inches or in cm.
>
>     However, there isn’t a property that allows us to use this same
>     approximation pattern for Dimensions.
>
>     The same advantages would apply:
>
>      1. We can have multiple declarative dimensions (10 inches, 25
>         centimeters) that approximate the true dimension, rather than
>         implying there are two different dimensions.
>      2. If we do not have this case, because the dimension is measured
>         very accurately and has only a single numerical
>         representation, then we can simply use a single Dimension.
>
>     This is also useful for conservation when the same dimension is
>     measured to different degrees of accuracy with different
>     instruments or techniques … there is only a single height (for
>     example) but it is measured with a laser, or by estimation.
>
>     Thus I would like to propose the addition of a new property,
>     Pxxx_approximates_dimension, that mirrors P189_approximates, that
>     would be used to associate true dimensions with their approximations.
>
>     It would be used in exactly the same way as P189:
>
>     painting a Human-Made_Object ;
>
>     has_dimension [
>
>         a Dimension ;
>
>     p2_has_type <aat:height> ;
>
>     pxxxi_dimension_approximated_by [
>
>             a Dimension ;
>
>     p90_has_value 10 ;
>
>     p91_has_unit <aat:inches>
>
>         ]
>
>       ]
>
>     Thank you for your consideration of this issue!  I’m happy to
>     write up a draft scope note for discussion if the general issue is
>     considered to be worthy of inclusion.
>
>     Rob
>
>
>
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> -- 
> ------------------------------------
>   Dr. Martin Doerr
>                
>   Honorary Head of the
>   Center for Cultural Informatics
>   
>   Information Systems Laboratory
>   Institute of Computer Science
>   Foundation for Research and Technology - Hellas (FORTH)
>                    
>   N.Plastira 100, Vassilika Vouton,
>   GR70013 Heraklion,Crete,Greece
>   
>   Vox:+30(2810)391625
>   Email:martin at ics.forth.gr  <mailto:martin at ics.forth.gr>   
>   Web-site:http://www.ics.forth.gr/isl  
>
> 	
>
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>

-- 
------------------------------------
  Dr. Martin Doerr
               
  Honorary Head of the
  Center for Cultural Informatics
  
  Information Systems Laboratory
  Institute of Computer Science
  Foundation for Research and Technology - Hellas (FORTH)
                   
  N.Plastira 100, Vassilika Vouton,
  GR70013 Heraklion,Crete,Greece
  
  Vox:+30(2810)391625
  Email: martin at ics.forth.gr
  Web-site: http://www.ics.forth.gr/isl

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