Many thanks,
Rob
[1]
https://www.metmuseum.org/art/collection/search/455545?&searchField=All&ft=*&offset=0&rpp=20&pos=12
[2] http://www.getty.edu/art/collection/objects/34663/
[3] https://collections.mfa.org/objects/58904
[4] https://www.nga.gov/collection/art-object-page.4217.html
*From: *Martin Doerr <[email protected]>
*Date: *Wednesday, October 16, 2019 at 11:18 AM
*To: *Robert Sanderson <[email protected]>, "[email protected]"
<[email protected]>
*Subject: *Re: [Crm-sig] NEW ISSUE: Approximate Dimensions
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 <[email protected]>
<mailto:[email protected]> on behalf of Martin Doerr
<[email protected]> <mailto:[email protected]>
*Date: *Wednesday, October 16, 2019 at 8:18 AM
*To: *"[email protected]" <mailto:[email protected]>
<[email protected]> <mailto:[email protected]>
*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
_______________________________________________
Crm-sig mailing list
[email protected] <mailto:[email protected]>
http://lists.ics.forth.gr/mailman/listinfo/crm-sig
--
------------------------------------
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:[email protected] <mailto:[email protected]>
Web-site:http://www.ics.forth.gr/isl
*CAUTION: This email originated from outside of the Getty. Do not
click links or open attachments unless you verify the sender and
know the content is safe.*
--
------------------------------------
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:[email protected] <mailto:[email protected]>
Web-site:http://www.ics.forth.gr/isl
*CAUTION: This email originated from outside of the Getty. Do not
click links or open attachments unless you verify the sender and know
the content is safe.*
_______________________________________________
Crm-sig mailing list
[email protected]
http://lists.ics.forth.gr/mailman/listinfo/crm-sig
