Comments to the working draft 4 of DM

These comments are respect to the DM working draft 4, 
accessed on February 17, 2011.

First of all, as my first time of reading the DM working draft, with my 
very fresh pair of eyes, I would like to say well done to the group. 
There are a lot of very interesting ideas in the model document, clearly 
reflecting a lot of deep thinking about the problem domain. And I like 
very much the position of the DM as for an interchange language. So well 
done, guys!

However, if the main goal of this new version of the working draft is to 
simplify what we had, particularly to enable "an upgrade path, from 
'scruffy provenance' (term TBD), to 'precise provenance' (term TBD)", I 
am not sure this goal was achieved!

Here are what I think and why:

1. In the introduction section, there is no such introduction about 
'scruffy provenance' (term TBD), or 'precise provenance' (term TBD). I 
think this is a key that should be brought in the front, and which 
should be used to structure the rest of the document. And this is not 
the case atm, IMO.

2. The Overview section: I am not sure I see much difference between 
this section and the section giving definitions to the 'core'. I would 
rather expect to see an overview of the model, for example, for the 
scruffy and precise level, what terms and properties we have at each 
level etc. I am sure Luc knows that the overview diagram needs update 
and I couldn't read the figure properly even printed the doc with 
high-resolution laser printer:)

3. I used the terminology of "terms" and "properties", but actually I 
don't what this data model is. What do we mean by "data model"? Is it a 
conceptual model, logical model, entity relationship model, or something 
else? It's not clearly stated and I am confused what terminologies I 
should used when referring to the model:(

4. The Example section: Would it be a good idea to define an example up 
in the front and use it throughout the whole document? I don't find a 
description about an example in this section and I found it hard to 
follow the 'examples' given in Section 3. And in the rest of the 
document, examples from many different scenarios are used. I wonder 
whether that prevents us from simplifying the reading of the spec.

5. Section 4, the PROM-DM Core: There are a lot of repetition with the 
overview section. And I wonder what we mean by "core". The core almost 
includes "all" the DM terms (apart from the few in section 5). My 
understanding of "core" would be really the essential set of DM terms 
that are must-haves to express the minimal provenance. IMO, the current 
"core" is rather inclusive, and provides constructs that can be used to 
support some rather complex provenance expressions.

If we can agree on the notion of "scruffy" (minimal??) and "precise" 
(extended??), maybe the core part can be used to correspond to the 
"scruffy" part, and make it lighter, more succinct, and easier and 
quicker to grasp and follow?

6. There are many cross-references that don't quite work in the current 
working draft, like saying some terms are mentioned in the previous or 
another section. I didn't include these problems here because I think 
these were caused by the re-structuring. I could list them out once the 
structure gets more stable.

7. There are also some technical points that I marked down in the 
review, which I didn't raise here either, because I am 'new' to the 
group and I don't want to re-open closed issues. What's the stage of the 
technical part of DM? Are there still open technical discussions?

In my opinion I think the document still needs some more work on the 
structuring and organization front to make it simplified.

I think we should make a better use of the notion of "scruffy" 
(minimal??) and "precise" (extended??), and use this to guide the 
restructuring of the document.



-- Jun

Received on Sunday, 19 February 2012 19:15:19 UTC