Re: [xml-dev] What is Data?

[Frank Manola <fmanola@acm.org>]

Roger--

I'd echo some of the other replies and suggest you think about what  
level of abstraction and perspective you're after.   To illustrate  
this, consider some examples.

1.  You say:

> The following description of a book is not data, although it  
> contains data:
>
>    In this groundbreaking book, evolutionary
>    biologist Jared Diamond stunningly dismantles
>    racially biased theories of human history by
>    revealing the environmental factors actually
>    responsible for history's broadcast patterns.

But this is a "description of a book", and thus an entity isn't it?  I  
could have a diagram representing this:

[some representation of the book]  ----description--->  ["In this  
groundbreaking book, ..."]

which seems reasonable enough.  But you also say:

> When you represent an entity, you've created data.

So isn't this text, which seems to me to be the representation of an  
entity, data according to this?

2.  Similarly, you say:

>
> This is not data and it contains no data:
>
>    Run really fast.

But suppose "Run really fast" is Rule #1 is a list of rules titled  
"What to do when when you encounter a bear in the woods" (I'm not  
saying it's a *good* rule!).  Again, that makes it the representation  
of an entity (a rule).  So isn't it data?

More generally, you seem to be to some extent taking the perspective  
reflected in the Wikipedia entry on data:  "Data are pieces of  
information that represent the qualitative or quantitative attributes  
of a variable or set of variables. Data (plural of "datum", which is  
seldom used) are typically the results of measurements and can be the  
basis of graphs, images, or observations of a set of variables. Data  
are often viewed as the lowest level of abstraction from which  
information and knowledge are derived."  But that's not necessarily  
the perspective that everyone takes.  A lot of people, in particular,  
munge "information" and "data", or take the view that "data" is  
anything you use to represent "information" in a machine.

I'd also note that this characterization of data as entities,  
attributes, and relationships (or entities and relationships if you  
prefer) comes (largely) from people who were already doing "data  
modeling", so they already tended to think in terms of stuff you stick  
into a database.

--Frank

On Aug 31, 2009, at 8:23 AM, Costello, Roger L. wrote:

>
> Hi Folks,
>
> Below is a definition of data, based on our recent discussions. I  
> ask for your comments on these aspects:
>
>    1. Is the definition factually correct?
>
>    2. Is it general? Are there any hidden assumptions
>       that restricts the generality of the definition?
>
>    3. Is it complete? Is there anything else you would
>       add to the definition?
>
>    4. Is it clear and easy to understand?
>
> /Roger
>
snip