- From: Gofran <gofran.shukair@deri.org>
- Date: Wed, 24 Oct 2012 23:35:29 +0100
- To: Phil Archer <phila@w3.org>
- Cc: Richard Cyganiak <richard@cyganiak.de>, Public GLD WG <public-gld-wg@w3.org>
*redirecting to the mailing list* On 23 Oct 2012, at 18:16, Phil Archer wrote: > I have a lot of sympathy with this. > > When I first was tasked with creating the RDF schema for ADMS, I > used a load of DCAT properties and only introduced a few new ones. > It was the introduction of a third related vocab (called ADMS for > Software, ADMS.SW, which is not on the GLD work list) that I came up > with RADion. That may or may not have been a sensible idea but it > seems to be in line with the sentiment here in that what we have are > two similar vocabs. They're slightly different because the people > that have created them have slightly different perspectives. > > DCAT is not designed, for example, to describe 3 separate PDFs > wrapped up in a zip file - ADMS is (among other things). > > But lest we get too hung up, perhaps we can take a little step back. > I've just made another couple of tweaks to the ADMS spec, RDF schema > and namespace HTML doc in readiness for Thursday (all linked from > the wiki). > > ADMS defines 5 classes and a bunch of properties that for the most > part have no direct parallel in DCAT. But... like DCAT, most 'ADMS > data' is Dublin Core. > > It's a difference of emphasis, a difference in approach and > therefore a difference in what gets included and not included in the > vocab. > > I see a number of options: > > 1. Spend time working to align DCAT and ADMS more closely (in which > case RADion is either a help or a hindrance - if the latter we don't > have to be bound by it). That *might* then lead to the kind of > integration we've done with RegORG and ORG. That's probably the > ideal but do we have time and and willingness? Also, very > significant effort has already been expended in creating ADMS and > ADMS.SW-compliant data. > > 2. Recognise that the overlap is significant but not a huge problem > in itself since so many of the properties used are from dcterms. The > ones that aren't are, of course, the more specialised ones. Cross > reference ADMS and DCAT and say "take your pick - and here's why you > might choose one over the other." Gofran's e-mail about re-usability > is helpful here I think, as would be a short text highlighting the > different approaches taken. I believe most potential users will feel > more comfortable with one or the other and the choice is generally > going to be made by repositories that harvest the data, not data > publishers looking for an outlet for their data. As well as W3C we > have national governments and fellow standards bodies publishing > ADMS data (Denmark, OASIS, Open Metadata Registry, GS1...). > I agree on this option , the overlap is significant and but also the use case difference is obvious as well. RADion still seems to be a good idea to me to embrace this for now > 3. If the WG feels either route above is not right for a Rec Track > document then we can publish ADMS as a WG Note and namespace doc and > more or less leave it at that. As you can imagine, I'd rather not > take this route but the WG is sovereign. > > Phil. > > > > > On 21/10/2012 17:29, Richard Cyganiak wrote: >> Hi Gofran, hi Phil, >> >> I think the fundamental problem here is that we have two specs that >> have a large overlap in scope, but neither is a subset of the >> other, and *probably* neither can be easily extended to cover the >> other without losing its focus. >> >> What is the overlap between both? >> >> Phil developed RADion in an attempt to “factor out” the overlap of >> both specs: repositories, assets, distributions. But I think that >> RADion fails to get to the essence of the overlap. It may be >> correct on the repositories and assets, but fails with the >> distributions, or at least has a conception of distribution that >> isn't sufficiently generic to properly cover DCAT. >> >> I think the overlap of DCAT and ADMS is that both are catalogs of >> metadata records designed for finding “assets” of some kind. They >> differ, however, in the kind of assets that are listed in the >> catalog, although there is overlap. >> >> Since the kinds of assets are different, there's a lot of >> difference in the metadata that is required to adequately describe >> them, and in the additional secondary concepts related to the >> asset, and in the relationships that need to be recorded between >> assets, and in the means of accessing the assets. >> >> I'm not suggesting any particular course of action as a result of >> this observation. We should closely study the overlap between >> DCAT's Catalog, Dataset, and CatalogRecord on the one hand, and >> ADMS' Repository and Asset on the other hand, and also study their >> relationships to things already out there. >> >> The more I think about it, the more I get worried that we're in the >> process of not just reinventing the wheel, but reinventing it >> twice, in parallel. >> >> Best, >> Richard >> >> >> On 20 Oct 2012, at 19:37, Gofran wrote: >> >>> Hi all, >>> >>> The sets of resources that ADMS and DCAT describe are intersected, >>> IMHO, I like to use the term "reusable" to point to the resources >>> that ADMS describes and the set of reusable resources include (but >>> not limited to) codelists, taxonomies, datasets ...etc as long as >>> they can be reused in a diffrent context and the ADMS purpose is >>> to facilitate this by describing them using the right terms. >>> >>> A dataset in data.gov.uk for instance is basically a useful >>> dataset for certain applications but it is not a reference dataset >>> and DCAT should be used to describe it. >>> While a dataset about the languages in the EU is certainly more >>> like a reusable asset that has broader usage base and ADMS and/or >>> DCAT can be used to describe it (though it is not a "semantic" >>> asset per se) >>> >>> The problem as I see it , how to extend ADMS (or DCAT or both) to >>> describe this difference . >>> >>> On 20 Oct 2012, at 14:17, Richard Cyganiak wrote: >>> >>>> Hi Phil, >>>> >>>> On 18 Oct 2012, at 18:33, Phil Archer wrote: >>>>> "ADMS, the Asset Description Metadata Schema, is a vocabulary >>>>> for describing so-called Semantic Assets, that is, things like >>>>> standards, code lists and taxonomies. Although it has a lot in >>>>> common with the Data Catalog vocabulary [DCAT], notably the >>>>> extensive use of Dublin Core [DC11], someone searching for a >>>>> Semantic Asset is likely to have different needs, priorities and >>>>> expectations than someone searching for a data set and these >>>>> differences are reflected in ADMS. In particular, users seeking >>>>> a Semantic Asset are likely to be searching for 'a document' — >>>>> something they can open and read using familiar desktop >>>>> software, as opposed to something that needs to be processed. Of >>>>> course this is a very broad generalization. If a code list is >>>>> published as a SKOS Concept scheme then it is both a Semantic >>>>> Asset and a dataset and it can be argued that all Semantic >>>>> Assets are datasets. Therefore the difference in /user >>>>> expectation/ is at the heart of what distinguishes ADMS from >>>>> DCAT." >>>> >>>> I have a number of issues with this. >>>> >>>> 1. You describe the purpose of ADMS as: “It's for describing >>>> things like standards, code lists and taxonomies.” This is too >>>> fuzzy. You can't have weasel words such as “like” in the sentence >>>> that states the purpose of a technology. Law texts are a bit like >>>> standards, right? So ADMS is for describing them too? >>>> >>>> 2. The text implies that the kinds of things described in DCAT >>>> cannot be “open and read using familiar desktop software”. This >>>> is not the case. In most data catalogs, the most common formats >>>> are CSV and Excel. >>>> >>>> 3. It is not particularly likely that code lists and taxonomies >>>> -- things that ADMS is intended to describe -- can be opened and >>>> read in familiar desktop software. >>>> >>>> 4. If the main difference is indeed one of user expectation and >>>> not one of vocabulary semantics, then a catalog-level flag in >>>> DCAT might be sufficient to eliminate the need for ADMS. Surely >>>> it is not that easy. So I don't feel that the text above gets to >>>> the heart of the difference between DCAT and ADMS. >>>> >>>> 5. It is somewhat open whether the “distributions” in DCAT are >>>> all machine-readable. There is an open DCAT issue about renaming >>>> “distribution” to “resource” and allowing pretty much arbitrary >>>> related online artefacts, including documentation and the like. >>>> >>>> Best, >>>> Richard >>>> >>>> >>> >> >> >> > > -- > > > Phil Archer > W3C eGovernment > http://www.w3.org/egov/ > > http://philarcher.org > +44 (0)7887 767755 > @philarcher1
Received on Wednesday, 24 October 2012 23:04:36 UTC