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Primer review, part 1 Introduction, Orientation sections

From: Alan Ruttenberg <alanruttenberg@gmail.com>
Date: Mon, 21 Jan 2008 01:47:32 -0500
Message-Id: <0A9A585C-B6EA-4C85-B599-89E98C122A69@gmail.com>
To: OWL Working Group WG <public-owl-wg@w3.org>

These comments are on the Primer document http://webont.org/owl/ 
documents/primer.html as accessed late night 1/20/2007. They are  
detailed comments on the Introduction an Orientation sections. Review  
of other sections will follow.

Summary:  There are a number of places where I think the descriptions  
don't adequately introduce OWL from the point of view of someone  
embedded in the technology described, which I think is important for  
drawing readers in. Ideally the orientations would make affirmative  
statements about why people coming from experiences with their  
technology might be interested in OWL, and what they should not  
expect to find.

Comments below are intended to be in order of presentation in the  
document. Both major and minor comments are included. To make things  
clear, I write this not from the point of view of chair, but from the  
point of view of OWL practitioner and educator.

----

ontological information

I don't find the adjective "ontological" helpful.

----

about individuals, classes, and properties
->

about individuals, classes of individuals, and properties that are  
used to relate individuals and classes to each other.

Note: Use of "individuals"  versus "instances" might be noted, as the  
latter is more commonly understood.  While they are not the same, the  
point of view that makes them different is worthy of note is important.

----

s/approachable// - let the reader decide that or say it was intended  
to be approachable.

----

OWL provides a rich language for structuring and classifying with  
both complete and incomplete information

What is classifying? (speaking as someone knowing nothing, and  
reading from the start of the document)

----

"OWL groups information into formal ontologies" Formal ontologies too  
strong - there are other uses (soduko) and arguments about what makes  
an ontology "formal".

I think you want to explain that OWL "documents" are called  
"ontologies" and that they provide a way to ....

Note also that OWL is a label for a set of properties that are used  
outside OWL ontologies, such as owl:sameAs

----

Introduction doesn't mention important bits about design  
considerations for OWL - that it there are known algorithms that can  
give complete answers etc, and that is is designed to the most  
expressive language for which one can do this, and why it is  
important to aim for this.

----

misled -> use a less stimulating word

-----

the triple view is not typically a fruitful way of writing or  
understanding complex expressions.

->

reading triples encoding OWL statements not always a fruitful way of  
understanding the complex expressions that can be expressed in OWL.

-----


"how extra non-logical information is associated with parts of an  
ontology"

What is non-logical information? (speaking as someone knowing  
nothing, and reading from the start of the document)

----

"In contrast, OWL allows for -- and encourages -- operations that are  
not rooted so directly in the evident structure of an ontology."

+ such as ...
(checking consistency might be something good to mention here)

----

"both OWL and XML have an object oriented approach"

I don't consider OWL to be object oriented, and think this will  
confuse rather than help. If it is to be mentioned, then say in what  
way they have this orientation.

----

s/OWL is oriented toward more abstract, higher level conceptual  
modeling than is XML. //

----

"relationships between descriptions" -> "relations between the things  
described"

----

"is oriented toward a more concrete level of conceptual modeling"  
don't know what this means. Be more explicit.

----

If Xml schema's core mission is validating XML documents, shouldn't  
the discussion start rather than end there?

----

"Both OWL and databases (either relational or object-oriented) can be  
used to store and organize data. However, databases are much more  
oriented towards this mission"

What is data, and how is it different from information? Saying that  
databases are more oriented towards storing and organizing data is  
too broad. They can organized and store certain kinds of information,  
and use it in certain ways.

Or:  "However, databases are much more oriented towards this mission,  
and in an environment where complete information is available (at  
least as far as applications are concerned)"
->
However databases are oriented to an environment where all  
information that an application needs is available, where  
considerations of data integrity in situations of simultaneous access  
and update are important, and/or where very large amounts of data  
needs to be worked with.

Database use does not imply negation as failure. It doesn't offer any  
support one way or another it seems to me, whereas OWL offers support  
for querying over information that is not explicit and not fully  
specified.

There is no mention of very important difference, namely that there  
are no integrity constraints in OWL.

----

OWL is more oriented towards flexible and expressive description of  
data (or information), i.e., ontologies, and performs in an  
environment where information is considered to be incomplete unless  
information to the contrary is known.

->

"OWL is more oriented towards flexible and expressive description of  
data (or information), and makes the assumption that information is  
incomplete unless information to the contrary is stated."

----

"It is this difference in completeness that most distinguishes OWL  
from databases, driving the different capabilities of OWL and  
databases. Users who treat OWL information as complete where  
completeness cannot be assured are very often surprised and confused.  
(Similarly those who use database technology in situations where  
information is incomplete can be similarly surprised and confused.)  
Applications that incorrectly make assumption about completeness can  
come up with patently incorrect results."

I don't think this will reach typical database users. It is too  
theoretical. It needs to be more down to earth. Clearly there are  
very obvious differences - transactions, triggers, replications - a  
whole set of considerations that OWL does not deal with.

I think you want to say something about why someone who has worked  
with databases would want to work with OWL.

----

"Ontologies in OWL are much more powerful and flexible than database  
schemas."

Perhaps the focus should be made, from the start, on comparing OWL to  
Database schemas, and pointing out that people who struggle with  
expressing what they need to say in database schemas are the sort who  
may be most interested in learning what OWL can do.

Other than this starting sentence, I don't think what followed after  
was expressed particularly effectively, given the audience.

----

Object-oriented Programming.

Again, focus on information completeness won't resonate with oo  
types. First they have to be told the "further stuff" and then why,  
despite this, they might be interested in OWL.

----

One person's view, hope it helps,

Alan
Received on Monday, 21 January 2008 06:47:45 GMT

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