RDFTM comments: Noy

This posting contains the editors' resolution of comments on the RDFTM
Survey posted by Natasha Noy:
http://lists.w3.org/Archives/Public/public-swbp-wg/2005Feb/0172.html

When discussing specific issues, please use the issue ID as part of
the Subject: line.


* RDFTM-NN001: Accepted with comments
|
| First, I felt a bit odd with the fact that the document is too much of
| a literature review to be a W3C working note (at least to my gut
| feeling). Many passages in the document, are along the lines of "[XYZ
| 2004] starts the paper by reviewing other approaches and then goes on
| to do x", "he doesn't present a diagram of this in the paper, but",
| etc. I almost had the feeling of "who cares?" It seemed to me that the
| note should focus more on the approaches themselves than on the papers
| that represent the approaches. It also seems a bit subjective and I
| would be interested to know what other reviewers think (I know that
| Mike Uschold is also reviewing this, in addition to me and David). This
| issue of being objective and non-judgmental has been raised before
| viz-a-vis other WG notes. Since  the WG documents are often scrutinized
| for objectivity and can be treated by some as endorsements, I would be
| a bit more careful about this.

The authors of the survey believe that the "literature review" is
useful in this context since the people whose work is surveyed are an
important part of the audience for this document. In most cases, the
papers are all we have to go by and the goal was therefore to present
summaries of them that save other readers from having to try to read
all the material.

The authors of the Survey have worked hard to be as objective as
possible, but the purpose is to reveal the strengths and weaknesses of
the various approaches. Given that the authors have a viewpoint of
their own, some element of subjectivity is inevitable but we hope we
cannot be accused of being unfair.

The authors would appreciate specific feedback on any examples of
subjectivity that WG members find unacceptable.


* RDFTM-NN002: Accepted
|
| I would have also liked a better indication of why the specific
| approaches that you reviewed were chosen. For instance, the first one,
| by Moore, seems rather immature -- why even include it at all? This is
| not a journal paper that should cover everything possible after all.
| There are several other approaches that you omit for being immature,
| why not this. Some more detailed criteria on why specific approaches
| were chosen for detailed discussion would have been helpful.


* RDFTM-NN003: Accepted with comments
|
| On the overall structure, I think it would have helped a lot if the
| document started with some discussion of what the goal of such RDF/TM
| integration/translation is. Then the discussion of pros and cons of
| different approaches would feel more grounded. This information is
| technically there, in the three bullet points in section 4.1 on the
| consequences for reduced interoperability. But until this point (i.e.,
| through most of the document), it is unclear that what you are looking
| for is the ability of merging the data, vocabulary conformance, and the
| ability to write queries against the target model. I think this
| discussion should come at the very beginning of the document, and in
| some detail. Otherwise, the qualitative good/bad judgments that the
| document makes are somewhat puzzling since it is unclear what the goal
| is. Similarly, you give a lot of importance to the quantitative
| measure: how many RDF or TM statements you get. Without some goal of
| what you are trying to achieve, simply saying that "more is worse"
| seems somewhat unsubstantiated.

The description of the goals has been expanded somewhat to address
this comment. However the chronological order of exposition and the
fact that the initial proposals were relatively immature seems to
require that detailed examination of the issues involved be postponed
until after the description of each proposal.


* RDFTM-NN004: Rejected
|
| Another high-level point. I think the discussion would have been much
| easier to read (in particular to someone not very steeped in at least
| one of TM/RDF, such as myself) if the major issues section (2.2) was
| more detailed. Again, you come back to this discussion in the end,
| explaining what is difficult about these issues, but perhaps you could
| spend more time before moving on to specific approaches to explain what
| the difficulties are. This would basically mean moving a lot of text
| from section 4 to section 2, and rewording it slightly.

This would require a substantial rewrite of the survey which cannot be
justified given the size of the intended audience. The real problem
lies in the fact that the "issues" are discussed in two places rather
than one (sections 2.2.1 and 4.3). The sketchiness of the former is
indeed unsatisfactory but perhaps it is also unnecessary. The editors
are considering removing 2.2.1 altogether and focusing all discussion
of issues in section 4.3.


* RDFTM-NN005: Accepted with comments
|
| I really like the idea of test cases and this certainly makes the
| document very practical and useful. I would have liked to see more
| discussion though of why these particular test cases: presumably they
| should cover most of the major issues, no? Do they? Also, is there any
| reason why the test case for RDF2TM translation is different from the
| one for TM2RDF. Why not have both of them represent the Puccini opera?
| Then you can see the round-tripping (or lack of it) much more clearly.

The purpose of the test cases has been explained in more detail and
the suggestion to have them be the same has been accepted.


* RDFTM-NN006: Rejected
|
| Then, when discussing each of the approaches, I would simply focus on
| the gist of what they do (regardless of who they reference and which
| part of the paper they do this in), and, more specifically, how they
| address the major issues you identified in the beginning. I think
| putting the whole discussion at the end, gets the reader lost and,
| frankly, I forgot what the approaches were by the time I got to section
| 4. At the same time, at the end of each subsection of section 3, I was
| left wondering on how does this particular approach addresses those
| difficult issues. Also, when reading descriptions of each of the
| approaches,  I was really lacking small snippets of TM/RDF code
| illustrating the examples, before the test cases. This is most probably
| largely due to my very limited familiarity with Topic Maps, but I think
| such snippets would have been useful.

As explained above, the editors are considering merging 2.2.1 with
4.3, which will at least avoid causing false expectations. It should
also be noted that the target audience has been more carefully defined
to be people who are already familiar with both paradigms.


* RDFTM-NN007: Accepted with comments
|
| Finally, can the WG notes refer to results from proprietary products
| (such as some of the solutions that are only hinted at in the papers
| and are implemented inside Ontopia products)?

This was discussed and resolved at the Boston F2F. Commercial products
will be mentioned where appropriate, but sparingly.


* RDFTM-NN008: Accepted
|
| Before you use RDF2TM and TM2RDF for the first time, perhaps spell them
| out?


* RDFTM-NN009: Accepted with comments
|
| In section 1.2, I would remove the information on which other works
| each of the works references. It doesn't seem that this is really that
| salient an information to include in a 2-sentence description of the
| approach.

The purpose was to show how the proposals build on one another and to
indicate a progressive deepening of the communities' understanding of
the problem. The information will be removed in its current form and
expressed more succintly in another way.


* RDFTM-NN010: Accepted
|
| Your definition of completeness in section 2.1 seems to imply that an
| approach cannot be complete if it is only one-way, when you say that "A
| complete translation will by definition be reveresible". I don't think
| you mean the two-way requirement here (i.e., RDF2TM translation can be
| complete by itself), but perhaps you could make it more clear.

An attempt will be made to clarify this.


* RDFTM-NN011: Rejected
|
| In section 3.3.1, the paragraph that starts with "Interestingly, what
| appears to be a very opaque RDF" seems very subjective. I would suggest
| removing it.

Other reviewers have felt this observation to be pertinent. The
editors feel that it is both objective and relevant since it provides
a possible explanation for the approach taken by the proposal in
question.


* RDFTM-NN012: Accepted with comments
|
| In section 3.4, you often mention what Garshol discusses, but this
| sounds a lot more like a review of the paper than of a particular
| approach. The fact that the authors raises some difficult issues in a
| paper, but his approach doesn't solve them is probably out of scope of
| a WG note. Similarly, examples of translations for n-ary associations
| that Gentilucci proposes and then rejects as clearly wrong, probably
| don't belong in this note either.

In fact the author does solve (or attempt to solve) the difficult
issues in question, but the wording in the survey was confusing and
has been improved. The translations that Gentilucci et al reject are
felt to be worthy of mention since a large part of the survey is about
what *doesn't* work.


* RDFTM-NN013: Accepted
|
| I would be careful about statements like the following in section 3.6:
| "superset of the most popular proposed semantic web metamodels (viz
| XML, RDF, and Topic Maps)". I doubt we want any document coming out ot
| this WG to refer to XML as a semantic web metamodel, do we? Another
| contentious passage:
| "... is difficult because of RDFs "more primitive nature"".
| I know the primitive is the quote, but again, do we want these
| statements in the WG document? In fact, the note has lots of things
| like this that make it sound more colloquial than it really should
| (references to "before breakfast" and as an "evening's exercise" are
| another example.) I would suggest tightening things up a b it.


* RDFTM-NN014: Accepted with comments
|
| Minor point: where available, it would have been helpful to have URLs
| for references, particularly for the ones that are solely web
| documents, such as various reports from Ontopia.

The URLs were present as links. They are now also shown in clear text.



--
Steve Pepper <pepper@ontopia.net>
Chief Strategy Officer, Ontopia
Convenor, ISO/IEC JTC 1/SC 34/WG 3
Editor, XTM (XML Topic Maps 1.0)

Received on Friday, 18 March 2005 14:27:00 UTC