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Re: Clarifying word

From: Irene Polikoff <irene@topquadrant.com>
Date: Sun, 17 Apr 2016 13:47:19 -0400
To: <kcoyle@kcoyle.net>
CC: "public-data-shapes-wg@w3.org" <public-data-shapes-wg@w3.org>
Message-ID: <D33941AC.9B3E2%irene@topquadrant.com>
With respect to graphs, is something like this better?

RDF graph containing triples that represent shapes is called ³shapes


A set of triples representing shapes is called a ³shapes graph².

I am not certain what is the exact nature of the comprehension/clarity
problem here because I, for example, don¹t quite understand what the
sentence below means and the issues it is trying to highlight:

"It seems to me that a graph may have sub-graphs, and the subjects of
those may be instances of classes, but it's gotta be triples all the way

What does it mean for a graph to have sub-graphs and, even more
importantly, why do we care? What are ³those² in the ³subjects of those²?
Are they sub-graphs as in ³the subjects of sub-graphs²? If so, what are
³the subjects of sub-graphs²?

Irene Polikoff

On 4/17/16, 10:46 AM, "Irene Polikoff" <irene@topquadrant.com> wrote:

>Then, you should write something that works for you and see what others
>think of it.
>Once you move outside of very basic topics, judging clarity of language
>becomes very subjective. For any paragraph that seems perfectly clear to
>some, there will be others who'd find it inadequate in some way.
>Sent from my iPhone
>> On Apr 16, 2016, at 11:28 PM, Karen Coyle <kcoyle@kcoyle.net> wrote:
>> That doesn't work for me, because once again we have no definition of
>>"shape" other than saying that it is an instance of sh:Shape, which
>>makes it an instance of a class, and, AFAIK, an instance of a class
>>cannot "point to" anything. I'm also pondering how a graph can contain
>>instances of classes. It seems to me that a graph may have sub-graphs,
>>and the subjects of those may be instances of classes, but it's gotta be
>>triples all the way down. This seems to be a mixing of structure and
>>semantics. For now, let's get the triples well-defined, and then we can
>>worry about the semantics of classes.
>> kc
>>> On 4/16/16 7:35 PM, Irene Polikoff wrote:
>>> I think it is quite simple:
>>>  * A SHACL shape is an instance of sh:Shape. A shape points to
>>>    constraints (or conditions) an RDF node is compared against to
>>>    determine if it conforms to the shape. For example, a shape
>>>    example:Issue may point to two constraints: one that says that the
>>>    property example:submitter must have exactly one value and the value
>>>    must be a string and one that says that the property
>>>    example:submissionDate must have exactly one value and the value
>>>    must be a date.
>>>  * When an RDF node conforms to conditions specified by a shape it is
>>>    said to be valid against a shape.
>>>  * A shape can also define what RDF nodes are to be validated (checked
>>>    for conformance) against it. This is called a scope of a shape. When
>>>    a shape doesn¹t specify a scope, its scope is any RDF node.
>>> The specification also uses the following terminology:
>>>  * RDF graph containing shapes is called ³shapes graph².
>>>  * RDF graph containing data to be checked for conformance (validated)
>>>    is called ³data graph².
>>>  * When examples talk about specific nodes that are being checked
>>>    against a shape, they use a term ³focus node².
>>>  * A report produced as a result of checking RDF data against the
>>>    relevant shapes is called a "validation report".
>>> Irene Polikoff, CEO
>>> TopQuadrant, Inc. www.topquadrant.com <http://www.topquadrant.com/>
>>> Technology providers making enterprise information meaningful
>>> Blogs ‹ http://www.topquadrant.com/the-semantic-ecosystems-journal/,
>>> http://www.topquadrant.com/composing-the-semantic-web/
>>> LinkedIn ‹ https://www.linkedin.com/company/topquadrant
>>> Twitter - https://twitter.com/topquadrant
>>> On 4/16/16, 4:49 PM, "Karen Coyle" <kcoyle@kcoyle.net
>>> <mailto:kcoyle@kcoyle.net>> wrote:
>>>    I decided to take Peter's request that more people read through the
>>>    document, figuring that I would only be able to do a portion of it
>>>    before it got over my head. However, I haven't gotten very far due
>>>    what I presume is some of that lack of consistency that Peter has
>>>    mentioned.
>>>    The introduction (1.) has these sentences:
>>>    "SHACL groups descriptive information and constraints that apply to
>>>    given data node into shapes. This document defines what it means
>>>for an
>>>    RDF graph, referred to as the "data graph", to conform to a graph
>>>    containing SHACL shapes, referred to as the "shapes graph"."
>>>    "A shape may include a scope which defines which nodes in the data
>>>    graph
>>>    must conform to it. When a data node is checked for conformance to a
>>>    shape, that node is referred to as the focus node. The output of the
>>>    validation process is a validation report which indicates whether or
>>>    not
>>>    the data graph conforms to the shapes graph."
>>>    In these we have "shapes", "SHACL shapes", "shapes graph", "nodes",
>>>    "data nodes" "focus nodes".
>>>    Shortly thereafter we have "shape definitions", and a "shapes graph
>>>    that
>>>    defines these constraints has two shapes."
>>>    The main problem is the use of "shape/shapes" some times and "shapes
>>>    graph" at others, with the implication (but not stated) that a
>>>    graph" can consist of one or more "shapes." However, I'm not sure
>>>    what a
>>>    shape is in this context, since it is by definition in the form of a
>>>    graph.
>>>    Note also that the examples in that section consist of multiple
>>>    that is there is no subject that holds them together. I believe they
>>>    should have a symbolic "top node" that shows that they belong to a
>>>    single graph even though there are subgraphs.
>>>    I'm happy to write alternate text for some of this, but in this case
>>>    I'm
>>>    not clear on what is intended.
>>>    There are other areas where I can suggest better wording. I'd
>>>rather do
>>>    edits in a copy than try to explain them. Would that be ok?
>>>    kc
>>>    --
>>>    Karen Coyle
>>>    kcoyle@kcoyle.net <mailto:kcoyle@kcoyle.net> http://kcoyle.net
>>>    m: 1-510-435-8234
>>>    skype: kcoylenet/+1-510-984-3600
>> -- 
>> Karen Coyle
>> kcoyle@kcoyle.net http://kcoyle.net
>> m: 1-510-435-8234
>> skype: kcoylenet/+1-510-984-3600
Received on Sunday, 17 April 2016 17:47:56 UTC

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