- From: Alf Eaton <eaton.alf@gmail.com>
- Date: Thu, 29 Nov 2012 09:16:19 +0000
- To: Shlomo Sanders <Shlomo.Sanders@exlibrisgroup.com>
- Cc: "public-schemabibex@w3.org" <public-schemabibex@w3.org>
On 29 November 2012 06:32, Shlomo Sanders <Shlomo.Sanders@exlibrisgroup.com> wrote: > I am looking at this snippet that I got from schema.org > > <li itemprop="author" property="author" itemscope="itemscope" > itemtype="http://schema.org/Person" vocab="http://schema.org/" > typeof="Person"> > <span itemprop="name" property="name"> > <span itemprop="givenName" > property="givenName">Gerhild</span> > <span itemprop="familyName" > property="familyName">Wildner</span> > </span> > </li> > > How does itemscope="itemscope" help? The itemscope attribute is redundant in most places, when itemtype is also present; itemtype isn't a requirement, though, so itemscope is always used to mark the start of an object. > What is the purpose of having both itemprop and property? "itemprop" and "itemtype" are HTML5 microdata attributes, "property" and "vocab" are RDFa Lite attributes. > The following snippet appeared in mail from Jason Ronallo: > <span itemprop="author" itemscope itemtype="http://schema.org/Person" > itemid="http://id.loc.gov/authorities/names/n50016589"> > <span itemprop="name">J.D. Salinger</span> > </span> > > In this example itemscope appears with no value. Is that just typo? In HTML, attributes such as "itemscope", "checked", "disabled", etc do not need to have a value - values are only required in XML. > No vocab. Is that OK? > No property, just itemtype. "vocab" and "property" are RDFa Lite attributes, so are not required if the implementation is only using microdata. > > We agreed that itemid=http://id.loc.gov/authorities/names/n50016589 is what > we want but is optional, right? itemid is always optional, as far as I know. > > Shlomo > > > -----Original Message----- > From: Kevin Ford [mailto:kefo@3windmills.com] > Sent: Wednesday, November 28, 2012 17:31 > To: public-schemabibex@w3.org > Subject: Re: Three steps > > Just to add support to Jason's note, the "itemid" property he included in > his last example would be ideal, but not mandatory. > > We can model People/Organizations, and their relations to CreativeWorks, per > the current Schema.org guidelines. It's just that those libraries that do > not have the technological capability to either mint a URI for a > Person/Organization or make use of an already minted URI for the same can > omit the "href" or "itemid" property. In RDF terms, it just results in a > blank node. Perhaps not ideal, but perfectly acceptable. > > In any event, the examples at the bottom of http://schema.org/Book for > "Reviews" omit the "Person" itemtype construct altogether for a simple > lexical string. > > Yours, > > Kevin > > > > On 11/28/2012 09:52 AM, Jason Ronallo wrote: >> Richard, >> >> It seems to me that Schema.org is already relaxed about these kinds of >> problems. The value of the author property is _expected_ to be a >> Person or Organization. Consuming applications on the other hand >> should expect to get imperfect data, though. Even the Schema.org >> documentation for a book uses a relative URL from the href to refer to >> the author. Here's a >> snippet: >> >> <div itemscope itemtype="http://schema.org/Book"> >> <span itemprop="name">The Catcher in the Rye</span> >> by <a itemprop="author" href="/author/jd_salinger.html">J.D. >> Salinger</a> </div> >> >> But maybe this is a bug? >> >> As a consuming application I would also expect to see something like >> this where a string is used: >> >> <div itemscope itemtype="http://schema.org/Book"> >> <span itemprop="name">The Catcher in the Rye</span> >> by <span itemprop="author">J.D. Salinger</span> </div> >> >> But if you are an implementer, read the documentation, and all you >> have is an author name as a string, there is nothing keeping you from >> being more exact with that and doing something like the following. >> This is probably what the recommendation ought to be if you only have >> an author name as a string. >> >> <div itemscope itemtype="http://schema.org/Book"> >> <span itemprop="name">The Catcher in the Rye</span> >> by <span itemprop="author" itemscope >> itemtype="http://schema.org/Person"><span itemprop="name">J.D. >> Salinger</span></span> >> </div> >> >> If you also have some kind of identifier for the person, then you >> could add an itemid: >> >> <div itemscope itemtype="http://schema.org/Book"> >> <span itemprop="name">The Catcher in the Rye</span> >> by <span itemprop="author" itemscope >> itemtype="http://schema.org/Person" >> itemid="http://id.loc.gov/authorities/names/n50016589"><span >> itemprop="name">J.D. Salinger</span></span> </div> >> >> So while recommendations to the community would be to be as exact as >> possible there is no requirement that it be so strict. >> >> Jason >> >> >> >> On Wed, Nov 28, 2012 at 7:09 AM, Richard Wallis >> <richard.wallis@oclc.org <mailto:richard.wallis@oclc.org>> wrote: >> >> I’m stepping out of the thread that seems to have developed an all >> encompassing life of its own [Itemprop for person] to pick up on an >> issue identified in the recent contributions between Karen and myself. >> >> This is the example of how to represent the author when marking up a >> work (for now lets assume a book with person as an author). >> >> I said that the author property of the Book should be a URI to a >> description of a Person (either a local Person description that >> onward links to authority like VIAF, or a direct link to an >> authority). >> >> Karen, quite rightly came, back to say that a library may only have >> a string of characters for the author name so can not do what I >> describe. >> >> This sort of scenario leads me to suggest that we approach such >> descriptive challenges in a three step process: >> >> 1. How to describe what we have, using Schema as it is >> 2. What changes/enhancements, if any, to Schema could we propose to >> improve the description [and pragmatically expect the Schema >> group to accept] >> 3. Provide examples/recipes for how the markup would look in each >> case >> >> >> Applying this to the Book->author problem.... >> >> Step 1. >> schema:Book->author is a property that requires a link to a Person >> or Organization – not a literal string. Therefore example markup >> would require links to Person description either externally supplied >> or created locally on the fly. >> >> Step 2. >> We only have a string for an author name, so why not suggest that >> Schema relaxes the restrictions on Book->author to enable the use of >> strings. Taking account of the underlying philosophy behind Schema >> (Things not Strings), it is exceedingly unlikely that such a >> proposal would be accepted as it would break their related entities >> model of the world. >> >> Step 3. >> We need to provide examples of how we would markup various >> situations that would cope with my ideal view and Karen’s real >> situation of only having an author string – plus possibly a few >> in-between. I believe that it would be possible to satisfy Schema’s >> need for a Person description (in this case with only a name >> property) by creating a description in line on the fly. >> >> I am conscious that as a group we have not been good at sharing >> example markup – I include me in that, my RDFa is not as good as I >> would like it to be – how we rectify this is something I ant to >> address in the next call. (tomorrow) >> >> ~Richard. >> >> > >
Received on Thursday, 29 November 2012 09:17:06 UTC