Re: alternate example in primer

Luc,

On Nov 13, 2012, at 9:46 AM, Luc Moreau <L.Moreau@ecs.soton.ac.uk> wrote:

> Hi,
> 
> When preparing the PROV tutorial at ISCW'12, we discussed the example for alternate in the primer.
> 
>   , if a file is copied from one directory to another, we may want to say that (according to our model) these are both the same file, just in a different location. We may say that the file in the first directory, F1, is an alternate of the file in the second directory, F2. Note that it is the context (location) rather than content of the file that differs between the entities in this case.
> 
> We didn't find this example as the most compelling. 
> 
>  I don't think that in general, copying a file creates  an alternate. If file f2 is a copy of file f1, I don't know what same thing, f1 and f2 present a same aspect of.


Both files are specializations of an entity that presents the fixed aspect of a given sequence of bits.
The two specializations further [differently] fix the file path aspect.


> And while there is some form of caveat "accordign to our model", this example may be confusing for readers.


Not sure if "according our model" is support to change the example. That phrase could easily be removed, since it isn't really qualifying anything (since our model is assumed).

> 
> Instead of this example, we decided to use a content negotiation example:
> 
> Dereferencing a url requesting different mime types eg. turtle or rdf/xml, returns two entities that are alternate of each other.


This is an even more abstract analog of the current "file copy" example. (c.f. "item vs. manifestation" and "manifestation vs. expression" in Jim McCusker and my FRIR IPAW paper)	


> 
> If we are in agreement, can we change the primer accordingly?


Or, just add it?

-Tim


> 
> thanks,
> Luc
> 
> 
>  -- 
> Professor Luc Moreau
> Electronics and Computer Science   tel:   +44 23 8059 4487
> University of Southampton          fax:   +44 23 8059 2865
> Southampton SO17 1BJ               email: l.moreau@ecs.soton.ac.uk
> United Kingdom                     http://www.ecs.soton.ac.uk/~lavm
>