Re: Southampton Pub data as linked open data

Chris Bizer wrote:
> 
> Hi Bijan,
> 
> please don't unsubscribe from the Semantic Web mailing list.
> 
> I'm a big fan of having structured data with clear semantics published
> on the Web. The clearer the semantics the better.
> 
> It would be great if we would have all data sources that are currently
> listed at programmableweb.org online as Linked Data and if the data
> and its schemata would be represented using OWL.
> 
> My argument was driven mainly from the deployment and education point
> of view.
> 
> When I talk to the people with a Web 2.0 background it is usually much
> easier to get them interested in Linked Data, RDF and RDFS as it is to
> get them interested in OWL. This might change in the future when OWL
> is used more on the public Web and when Web applications (like
> browsers and search engines) start to take advantage of OWL.
> 
> But for now, I think the right approach in order to address broader
> communities is to make using Semantic Web technologies as easy as
> possible for them and this (at least for me) currently does mean not
> to talk about OWL too much.
> 
> I'm happy to be proven wrong on this point.
> 
> Cheers
> 
> Chris
> 
> -- 
> Chris Bizer
> Freie Universität Berlin
> Phone: +49 30 838 55509
> Mail: chris@bizer.de
> Web: www.bizer.de
> 
> 
> ----- Original Message ----- From: "Bijan Parsia" <bparsia@cs.man.ac.uk>
> To: "Semantic Web" <semantic-web@w3.org>
> Sent: Wednesday, July 30, 2008 10:53 AM
> Subject: Re: Southampton Pub data as linked open data
> 
> 
>>
>> On Jul 30, 2008, at 8:44 AM, Chris Bizer wrote:
>>
>>> Hi Bijan and Richard,
>>>
>>> I think it would be helpful for this discussion to distinguish a bit 
>>> between the different use cases of Semantic Web technologies.
>>>
>>> Looking back at the developments over the last years, I think there 
>>> are two general types of use cases:
>>
>> I really don't accept this analytical framework. It has more than a 
>> bit of the just so story about it.
>>
>>> 1. Sophisticated, reasoning-focused applications which use an 
>>> expressive ontology language and which require sound formal semantics 
>>> and consistent ontologies in order to deliver their benefits to the 
>>> user. In order to keep things consistent, these applications usually 
>>> only work with data from a small set of data sources. In order to be 
>>> able to apply sophisticated reasoning mechanisms, these applications 
>>> usually only work with small datasets.
>>
>> The last two are just not true and very unhelpful. Can we stop there?
>>
>> (Consider the general work on tractable fragments. Consider the SHER 
>> work.)
>>
>>> 2. The general open Web use case where many information providers use 
>>> Semantic Web technologies to publish and interlink structured data on 
>>> the Web. Within this use case, the benefits for the user mainly come 
>>> from the large amounts of Web-accessible data and the ability to 
>>> discover related information from other data sources by following RDF 
>>> links.
>>
>> I don't think I believe this either. And least not in the substantive  
>> claims that follow.
>>
>> (Check out the Tambis and the DL Lite papers. Tambis is *exactly* 
>> about using ontologies to provide better *user* experience of 
>> navigating over multiple, independent data sources. DL Lite is 
>> *designed* to handle the data integration case wherein you can leave 
>> your data in the original RDBMSs and yet have a view that is more 
>> "conceptual" (and intuitive) which also allows for proper distributed  
>> query.)
>>
>>> For each type of the use cases, there is usually a different set of 
>>> technologies applied. OWL and classic heavy-weight reasoning for the 
>>> first use case. HTTP, RDF, RDFS and light-weight smushing techniques 
>>> for the second use case.
>>
>> A more useful, imho, categorization is that there are several 
>> different sorts of task, e.g.,:
>>
>> 1) determining what to present (and how)
>> 2) modeling
>> 3) determining how to navigate
>> 4) mapping and otherwise meshing
>>
>> All of these occur in ontology land. Indeed, 2 is usually *in service* 
>> of the other ones. (Please check out Alan's slides I referenced earlier.)
>>
>> Forget OWL exists. I think I would *still* have a problem with the 
>> merge of all these roles that you see with things like subpropertying  
>> rdfs:label.
>>
>>> In the first use case, people think in terms of "ontologies", for 
>>> instance a basic concept in OWL2 are ontologies. In the second use 
>>> case, classes and properties are mixed from different vocabularies as 
>>> people see fit and are related to each other by RDF links.
>>
>> I don't see how the latter follows from anything about the second use  
>> case. At least not in a non-tendentious manner.
>>
>>> The second use case is inspired by the Web 2.0 movement and aims at 
>>> extending the web with a
>>> data commons into which *many* people publish data.
>>
>> Many people publish Web data without understanding or even knowing the 
>> existence of HTML. Most people who *publish* data in the world (a  lot 
>> of people!) having considerable data modeling and data format  skills. 
>> I really don't see that RDF is so much better off than many  of these 
>> (having worked with very non-data-literate people).
>>
>>> As it is not very likely that all these people will be logicians and 
>>> understand (or are interested in) the formal semantics behind the 
>>> things they do,
>>
>> Most people writing OWL ontologies are not logicians. It's kind of 
>> hard to take your analysis too seriously if you elide this basic fact.
>>
>>> people (including me) working on the second use case are often a bit 
>>> critical about too tight formal semantics and extended public 
>>> discussions about minor details that arise from some specs.
>>
>> Funny, I've been trying over and over to move this discussion into 
>> "What would be a more useful presentation mechanism" or "What are the  
>> real requirements of a labeling system". Why not engage *that*?
>>
>>> These discussions have been a mayor obstacle to deploying the 
>>> Semantic Web over the last years as they drive away people away from 
>>> using the technologies.
>> [snip]
>>
>> *Really*. Are you kidding? On what evidence do you base this?
>>
>> More of an obstacle than "RDF is magic and so much better than XML 
>> because it does magic merging" lines? Do you follow the HTML world and 
>> how it views RDF (based on, for example, the RSS and Mozilla 
>> experiences)?
>>
>> I mean, a good chunk of the Web world spends its time arguing about 
>> the semantics of elements in fussy detail. (When do you use abbr? What 
>> is an alt text exactly?)
>>
>> So, sorry, I've experienced your line as a *constant drumbeat* since I 
>> started working on the semantic web and it just seems to be a "shut  
>> up and don't think" line rather than a serious empirical analysis.  
>> There's nothing novel about it, afaict, nor is there any substantive,  
>> grounded content to it, afaict.
>>
>> Note this *does not mean* I am, in fact, the straw man people seem to  
>> want me to be. I'm *not* arguing that OWL or the logical core of OWL  
>> is the be all and end all of *anything*. I try hard to find specific  
>> descriptions of when OWL is a large win for its users and try to  
>> steer people away from OWL (or RDF or XML) when it's not right for them.
>>
>> I've been spending a *huge* amount of time trying to get decent 
>> annotations into OWL and do you know what the biggest, the single 
>> biggest, barrier is? Serializing them into RDF. Just trying to get 
>> annotations on annotations (of arbitrary depth) is a real nightmare 
>> (yet trivial in XML :().
>>
>> Sigh. Perhaps it's time to unsubscribe to this list. The reflexive OWL 
>> bashing is getting to me. As is the implicit  and sometimes explicit) 
>> arguments from I'm-in-the-cool-group-and-you're-not. I don't know why 
>> it's so hard to grasp that someone can be both a logician *AND* 
>> seriously engaged in human factors, but here I am.
>>
>> Or not. If you'd like further replies from me, please send to my 
>> address directly.
>>
>> Cheers,
>> Bijan.
>>
> 
> 
> 
Please reply.

Jude

Received on Thursday, 2 October 2008 11:00:59 UTC