What does this mean to the Semantic Web Community which has  been working on a smarter web in the last decade?
Well, a lot… First of all, it´s good to hear that Google will continue to develop Freebase as a free and open database to everyone, saying “… we would be delighted if other web companies use and contribute to the data.”

Until yesterday still a lot of companies were not fully convinced if the Semantic Web will play a central role in the further development of the Internet. Now the game has changed. The entity-driven approach to develop web applications has just started now:

We will keep on reporting and discussing how Google will influence the development of the Semantic Web – and if I had a wish for free: Please add RDF(a) to the Freebase widgets!

Semantic Web

Jamie Taylor, Metaweb

Andreas Blumauer from Semantic Web Company (SWC) talked with Jamie Taylor, Minister of Information at Metaweb Technologies Inc. about Freebase & Linked Data and Google´s announcement to use RDFa.

SWC: At ISWC 2008 Freebase became “officially” part of the LOD Cloud. What exactly has changed since that time?

Jamie: Since Freebase is a community writable semantic database, the addition of the RDF interface allows anyone to publish data into the LOD cloud. LOD Applications can access any Freebase Topic through the RDF interface by constructing a URI from the Freebase identifier.  But perhaps more importantly, because entities in Freebase can be annotated with multiple identifiers, Freebase Topics can be retrieved by constructed URIs using the identifiers used by other systems and data sets.
For instance, the movie Blade Runner can be referred to as http://rdf.freebase.com/ns/en.blade_runner, but it can also be referenced as http://rdf.freebase.com/ns/authority.netflix.movie.70053131 using the Netflix identifier, http://rdf.freebase.com/ns/authority.imdb.title.tt0083658 using the IMDB identifier, or as http://rdf.freebase.com/ns/wikipedia.en.Dangerous_Days using a Wikipedia wikiword (which in this case is a Wikipedia redirect to the wikiword Blade_Runner).
Freebase also provides a user maintained mapping of how these identifiers can be used to address resources in other LOD systems. The sameas.freebase.com schema can tell an LOD user that the Freebase Blade Runner Topic can also be found in DBpedia using Wikipedia identifiers or how musical artists can be found at the BBC using Musicbrainz identifiers.  In fact, the Freebase RDF interface uses the sameas.freebase.com schema to create the owl:sameAs links in the RDF output allowing the user community to expand the interconnections between Freebase and the LOD Cloud.
Linked Data providers are also using the strong identifiers in Freebase to identify entities such as companies and locations in their own data sets.  When they find an entity that is not represented in Freebase, they simply add the entity to Freebase and use the newly minted Freebase identifier.  This permits anyone using their data to understand how their entities relates to any of the more than 5 million things interconnected within Freebase.

The RDF interface can also be used to reference the Freebase type system, giving LOD data set providers vocabularies across a wide range of subject areas.  And because anyone can expand Freebase’s data model, data providers can use our schema development tools to build and extend these vocabularies to suite their needs.
Freebase was not designed for ephemeral or fast changing data, like weather conditions or stock ticks.  But this type of information is well suited for publication as Linked Data.  Freebase entities representing a location or company can be annotated with references to LOD services that provide these types of volatile data.  Similarly, Linked Data provides a great way to disseminate very fined grained information that might be associated with a scientific study or financial report.  Linked Data provides a seemless transition from Freebase, where a user (or application) can run a query with constraints that run across a wide range of types to find entities of interest along with the LOD services that provide access to temporal or high resolution data not available in Freebase.
We recently demonstrated MQL Extensions which allows the Metaweb Query Language to use data from other systems as a part of the query constraint and result set.  While MQL Extensions are user extensible and work with a wide array of systems,  this capability makes the connection between Freebase and the LOD Cloud even more transparent.
For example, because US companies that are registered with the SEC are annotated CIK code in Freebase and the sameas.freebase.com schema indicates that the CIK annotation can be used to create a URI that is dereferencable at rdfabout.com, it is possible to write a MQL query that asks who is on the board of financial services companies that trade on NASDAQ and are  headquartered in California (and using another MQL Extension, you can ask for their stock price as well!)

SWC: Many organisations are very interested in Linking Open Data now but they are still not sure if they can benefit from publishing data on the web – what´s your experience so far?

Jamie: Linked Open Data provides a simple, standard way for organizations to distribute structured data.  For most organizations, providing access to data is another important outlet to announce the availability of higher value services.  For organizations involved in building or selling physical goods, the bits representing what they provide are not the goods themselves, but a way of attracting potential customers.  Making catalogs and specification sheets available in electronic form, so other applications can connect buyers to their physical goods is simply an effective marketing system.  Even for firms involved in electronic services, providing access to open structured data is generally a lead-in to value added services.  For instance, if I ran a service collecting hard-to-find information about manufacturing relationships between medium sized businesses, I would publish open company profiles covering things like market size, industry, location for the medium-sized businesses I tracked, so potential users the premium data would know I had the coverage they were looking for.

SWC: Just recently Google has announced to use RDFa to enhance their search results. What do you think?

Jamie: We are excited about Google’s announcement. Yahoo’s use of RDFa for Search Monkey and Google’s announcement gives RDFa users tangible benefits. The Search Monkey team was very quick to realize that because users can create data models in Freebase, and because the elements of those models all have strong RDF identifiers, Freebase provides a large and user extensible vocabulary for RDF/RDFa (see the list of vocabularies). When a user wants to create a Search Monkey application that works with their film review site, they need not invent a new vocabulary (that will probably be used only once),  they can use the Freebase Film Domain vocabulary which supports over 63,000 instances in Freebase alone.
Similarly, with over 5 Million well described Topics in Freebase and over 14,000,000 Named Objects (Topics, images, musical tracks and documents) when a user wants to unambiguously identify a subject or object in RDF/RDFa, Freebase has an extremely large collection of identifiers to draw from.  These cover people, places, companies, movies, music, books and wide variety of other subjects.  If Freebase doesn’t have the entity the user is looking for, they can of course add it themselves and make use of the identifier immediately. I think this is why Google used some Freebase identifiers in their examples. We hope that with Yahoo and Google’s support for RDFa the web will become a strongly annotated source of data which can support a wide range of user applications.

SWC: Thank you, Jamie!

Related articles by Zemanta

• Putting Freebase in a Star Schema (gen5.info)
• RDFa, Google (ivan-herman.name)

Andreas Blumauer from Semantic Web Company (SWC) talked with David Huynh, “Interaction Scientist” at Metaweb, the company which developed Freebase, an “open, shared database of the world’s knowledge”.

SWC: David, you have been working for MIT´s Simile Project and now for Metaweb Technologies – two “building blocks” of the Semantic Web. Could you tell us a bit about your ongoing work at Metaweb?

David: My official title at Metaweb is “Interaction Scientist,” and so my main focus is coming up with novel interaction designs for Metaweb’s platform and products, and prototyping them to some extent to evaluate their effectiveness. Parallax was one such prototype that has gathered much excitement within Metaweb and the Semantic Web community at large. And the Freebase query editor 2.0 shows my interaction designs at the other end of the spectrum – targeting developers rather than just end-users.
I’ve also learned that data-centric user interfaces and interaction designs can only be as good as the data allows them to. So I am also dedicating some of my time toward analyzing the data we have and improving its quality so that I can design even better interactions.

Freebase Query Editor 2.0 from David Huynh on Vimeo.

SWC: With Parallax you have introduced a new way to search and explore data: Could you explain the “set-based browsing paradigm”?

David: In the browsing paradigm of the original Web, while looking at a web page, you can only click on one hyperlink to get to one other web page. But in a lot of cases, the hyperlinks on that web page can be grouped into different groups based on what they mean to the human reader: these are the links that lead to reviews, these are the links that lead to authors, these are the links that lead to vendors, etc.
Now if the computer actually knows what these links mean, then you can tell it to follow several of those links that mean the same thing: follow all the links that lead to authors. Think of it as powered browsing: the computer does the work of following several similar browsing paths at the same time – going from a set of things (web pages or data entries) to a similarly related set of things – and making all of that information available for your perusal in one shot. It is a paradigm shift compared to how we browse the Web today. And it’s only possible when the computer is capable of telling which link is similar to which other link. And that capability, in turn, will be made possible by the Data Web.
(See this unpublished paper which goes into depth about this concept)

SWC: Linked Data is evolving fast. A huge amount of RDF data is available and ready for exciting new applications. Unfortunately, one bottleneck is still the availability of Semantic Web user front-ends which demonstrate the power of linked data. Do you think, that the Semantic Web is rather a server-technology than an end-user experience?

David: I have never thought of the Semantic Web as either a server technology or an end-user experience. I only care about usefulness, and then a matching amount of usability to make that usefulness accessible to people, especially those without Computer Science expertise.
I find that it’s so much easier to explain to people and get them excited about “immediate, personal, local benefits” of a particular technology than about “long-term, communal, global benefits” of a vision. For most people, the former must be experienced and felt often before the latter can appear vaguely appealing enough to call for actions. I’m lazy – I don’t like to spend efforts convincing people of visions; I only want entice people into using the tools that I have created.
So if Parallax is considered a success, it is so not just because of its technologies and research contributions, but also because the accompanying screencast explained it in a way that people who cared nothing about the Semantic Web could understand why Parallax would be useful to them. This was achieved by pointing out limitations of existing web technologies as already experienced and understood by a lot of web users, and then illustrating concretely a possible solution enabled by data web technologies.
Perhaps I could venture further and say that the dichotomy of server technologies and end-user experience is what’s holding back Semantic Web user interface efforts. For those who don’t have expertise in design, it is a comfort to think that once the back-end technologies are solid, then it’s just a matter of putting on some polishes, a.k.a. user interfaces from their point of view, to make the whole package appealing. This approach is wrong. The user interface design must inform the back-end design. Otherwise, the user interface will almost always reflect the internal system model, and that’s usually very dissonant with how users think and behave. Recall all the Semantic Web interfaces you have seen that force users to think in terms of triples or of raw URIs. Those were made by starting from the data model, not from user needs.

SWC: Quite often I hear people saying: Where is the Semantic Web? – I still can´t “see” it! How could the linking open data community make use of such user interfaces like Exhibit, Piggy Bank or Parallax? Is the set-based browsing paradigm a universal way to browse linked data or just one possible way?

David: My research prototypes embody a number of UI ideas that are quite transferable to other platforms. Most of my code is open source, too. This, by the way, is rarer than it should be: research prototypes often fall apart as soon as, or even sooner than, the relevant research papers get presented at conferences, and research code rots rather than gets offered free for reuse. This is sad, because reusable data needs reusable code to proliferate even more widely, but there is no reward system for making research code reusable, or for keeping research prototypes running. So perhaps people can’t “see” the Semantic Web because research prototypes are not presented in appealing and comprehensible ways, and they break down and disappear too quickly.
Regarding the set-based browsing paradigm, it is most certainly not the only way to browse linked data. It is just the first good one that came to my mind, around 2005. But it’s not until 2008 that I actually got around to implement it for real. One of the factors so important in its feasibility is the quality of data in Freebase, compared to other data sources that I had access to. Even the simple fact that a lot of Freebase topics have images makes Parallax look a lot more interesting and useful. People like to see pictures rather than raw URIs. And the diversity of types of data helps illustrate the browsing paradigm of Parallax – that ability to shift focus from one set of things to another set of things, even across very seemingly unrelated domains of information, such as from politicians to their celebrity friends in the movie industry.
So, perhaps one of the main challenges in adopting Parallax ideas on any arbitrary RDF data set is curating the data sufficiently for the purpose of presenting it. In fact, if you don’t know how some data is to be presented and used, there’s no way for you to determine if that data is of sufficient quality. User needs and interface designs drive back-end implementation and data curation, not the other way around. It’s a simple idea, really, but it can be hard to adopt if one is fixated on data alone.

SWC: Do you plan new versions of Parallax? When will it become part of Freebase or of even more Linked Data Sources?

David: I’ve done a few further experiments with the ideas in Parallax, but they are not ready for public use, yet. Freebase data makes my job much easier by allowing me to focus mostly on interaction designs rather than mostly on data quality, or rather, fighting the lack of data quality, for the purpose of presenting it. So I’ll start with Freebase data and we’ll see where it takes me.

SWC: What else are you working on at the moment?

David: As mentioned briefly earlier, reusable data needs reusable code to proliferate widely. That gives you a hint at an effort that I’m involved with.

SWC: Many thanks, David!

About David François Huynh

Related articles by Zemanta

• Linked Data In(ter)action (blogs.talis.com)
• Semantic Web Landscape 2009 (slideshare.net)
• LIS 653 Posters (slideshare.net)

Tetherless World sums up the Freebase facts (e.g. 156,000,000 assertions made; 1370 published types; 75 domains; graph model, identity, web based) and further points out that ontology creation “is a social process, and both freebase and semantic wiki are tools that enable users to create ontological vocabulary without worrying too much on building a comprehensive ontology.”

Inkdroid notes that the RDF service release “is important news because Freebase is an active community of content creators, creating rich data-centric descriptions with a wiki style interface, fancy data loaders, and useful machine APIs.” This is followed up by a quick and handy tutorial how you can get machine readable data back from freebase using a URI with Freebase. Conclusion:

So why is this important? Because following your nose in HTML is what enabled companies like Lycos, AltaVista, Yahoo and Google to be born. It allowed for agents to be able to crawl the web of documents and build indexes of the data to allow people to find what they want (hopefully). Being able to link data in this way allows us to harvest data assets across organizational boundaries and merge them together. It’s early days still, but seeing an organization like Freebase get it is pretty exciting.

Yves Raimond was the first to wonder on the public W3C LOD mailinglist: “now, to see whether it links to other datasets ” – the idea of having linked data without the linkage would indeed seem like love’s labour lost. Semantic Focus / James Simmons seconds: “One downside is the data doesn’t appear to link to external resources, in a sense walling itself in. It should be trivial to link the topics that came from Wikipedia back to Wikipedia as well as DBpedia (which would be killer, by the way).” This is followed up a later post, where James expresses concerns regarding the relationship DBpedia / Freebase: “Freebase may see a drop in userbase growth and participation if it becomes a mirror of DBpedia (or vice-versa) and the popularity once garnered by one project may shift towards the other, or away entirely.”

More News / Andrew Newman puts the Freebase RDF service release in context with Cathrin Weiss’ “250 million triples on your iphone” submission, iMoCo, to the Billion triples challenges, also DBpedia and Semaplorer, developed at the University of Koblenz:

DBPedia stood out because it was the only one that allowed you to write data to the Semantic Web rather than just read the carefully prepared triples. For a similar reason I though SemaPlorer was good because they tried to do more than just the standard triples but went that extra bit further by making it more generic like integrating flickr. But they were all excellent, all of them showing what you get with a billion or more triples and inferencing.

That combined with the guys at Freebase making all of their data available as RDF and it was a big day for the Semantic Web.

ARQtick / AndyS plays a bit with the Blade Runner example cited by Freebase, e.g. takes a look at the graph, looks for interesting properties and extracts author names

N.B. If you want to follow ARQtick’s example: use the Linked Data browser plugin Tabulator or go to the Marbles site to view the RDF – without a data browser you’ll be redirected to the HTML page. You will also need it to make sense of rdf.freebase.com.

Alan Dix is a Professor at the Computing Department of Lancaster University, and author (with Janet Finlay, Gregory Abowd, and Russel Beale) of Human-Computer Interaction.

To start with, Alan pointed to the two sides of achieving the web of data: Firstly generating the web of data (a billion triples, as mighty as this may sound, is actually tiny, says Alan) and then, secondly, accessing the web of data.

With regard to generating the Web of Data, Alan distinguished between top down and bottom up approaches, counting to the former the creation of the web of data from legacy sources (i.e. where you take existing data and semantically lift them, e.g. from structured data) or web scraping such as DBpedia‘s extraction of data from Wikipedia.

N.B.: This notion of ‘top-down’ does not imply a hierarchical relationship, but rather means that there is already a plan for what is going to be put on the web of data (e.g. ‘all semi-structured information on Wikipedia’ or ‘dataset XY from project Z’). The bottom-up idea here implies that data is added as the result of an action, or interaction, as the user/s go, e.g. relationships are created as the user expands his or her social network. For instance on Amazon, user interaction is used to generate semantics: People do not tell Amazon what they like, they simply buy it.

Having relationships of course does not imply yet that these relationships are part of the Semantic Web. Or, as Alan put it, “why should I be RDFizing my online presence if none of my friends are?”

Please take a look at the PDF of the Alan’s slides (2,4 MB) – what I cannot reproduce here is a chart he developed, which was very useful for describing current scenarios on the web and which posed a twofold question:

Does a website/platform have the web of data implemented? YES/NO
Is the web of data on ta website/platform apparent to the user? YES/NO

The possible combinations (YES/YES, YES/NO, NO/YES, NO/NO) provide a good heuristic tool for describing what is currently available, with and without the Semantic Web. Take, for instance, the shiny interface of Talis’ Project Cenote: Cenote’s vision is to “make library data visible in many contexts, inside and outside of the library, making the data much more accessible and visible to a wider audience – benefiting current and potential users of library services wherever they are.” On Cenote, the user doesn’t see that it’s got the Web of Dat in it – it is actually implemented, but not in a way that is apparent to the user.

On the other end of the spectrum, you have a platform like Facebook: Alan referred to Facebook as “the user’s own web of data”, i.e. web of relationships: The user is aware of these relationships (they actually shape his interaction and communication with the site), and the (numerous!) apps on Facebook continually add relationships, but, regrettably, insulated from one another and not using RDF (and don’t you try to take data out of Facebook!).

Two examples of public data that Alan cited and that grow as people/institutions add data do them are Freebase (the “open database of the world’s information” – see previous posts on this blog about Freebase) and Swivel. Swivel allows people, institutions, anyone to upload and explore data, also featuring official data sources such as (links go to their Swivel pages): New York Federal Reserve Bank, UNESCO Institute for Statistics, DukeResearch or EUROSTAT. According to Alan, there is already more data on Swivel now than in the whole Linked Data cloud.

Alan also mentioned the Social Graph API – o yesterday evening Luca Hammer (one of the web 2.0 people who had joined the Open Hacking Session) introduced me to the WordPress Plugin “Meet your commenters” – Meet you commenters uses Social Graph to find social relations on the web, and adds these data to the commenter profiles it creates in WordPress.

Image via WikipediaOn a different note: I took sometime today to explore Alan’s homepage and found the cute Christmas Cracker’s application which was first developed in 1999 and which is now also available on Facebook. As trivial as it may sound at first – sending virtual Christmas Crackers (with more than 5000 possible combinations!) is a good showcase for developing Human Interaction Scenarios, and a number of papers have been written about the application. Here is the casestudy which Alan recommends to begin with: Designing experience – virtual Christmas Crackers.

The abstract and a list of links to all websites and demos Alan discussed can be found here. Full reference: A. Dix and R. Cyganiak (2008). Using the Web of Data. Keynote at WOD-PD 2008 | Web of Data Practitioners Days, Vienna, Austria – Oct 22-23, 2008. http://www.hcibook.com/alan/papers/WOD-PD-2008/

Even if you have not met Richard Cyganiak in person, you have certainly come across one of his creations: The Linked Data Cloud. Richard is a research assistant at DERI Galway. In his demo, he gave us the opportunity to gain hands on experience, introducing a tool he dubbed Snorql, which is basically an easier to use version of a SPARQL-endpoint, as it already has the required prefixes ‘pre-installed’:

Using the Snorql interface, we could explore the dataset we had created collaboratively during Keith Alexander and Yves Raimond’s session. Writing SPARQL queries manually can be a challenge, but is next to impossible if you (like me) don’t know the syntax. But today we could just copy and paste all the queries from a website Richard had put up prior to his session – thanks a lot for the excellent preparation and demonstration!

Richard also showed a couple of RDF browsers in action, e.g. the Tabulator Plugin (“a Firefox extension which allows Firefox to handle data as well as documents”), or the Marbles Linked Data browser which is running right on beckr.org/marbles; enter, for instance http://api.talis.com/stores/wod-pd-sandbox/items/People/JanaHerwig (learn more about Marbles here).

Thank you, Alan and Richard – the combination of talk and demo was indeed a perfect intro towards using the Web of Data.

Related articles by Zemanta

• How will we interact with all this data?
• A New Constellation in the Linking Open Data (LOD) Sky

One answer lies in using mockups, which are, on the one hand, an indispensable instrument for prototyping user interfaces, but also valuable when it comes to explaining the workings of an application to an end-user, an audience of interested researchers or a client.

And when it comes to explaining a search engine or search widget, mockups are even more important, as we all and in particular end-users are often unable to think of search interfaces other than in terms of Google.

We have become so googlified that hardly anyone can think of different ways of searching for information than Google has offered for many years now: Put a couple of words in a text box, click a button and scroll through a list of titles and summaries. Repeat until you’re done, or try a new search and repeat. Wow!

Although even Google has started recently to implement a little bit of semantics by offering an auto-complete functionality on google.com (on some local versions like Google Austria this feature is still not available), even the most basic concepts for an intelligent search interface are still not part of common sense thinking.

Admittedly, there are people who get irritated instantly by complex user interfaces like David Huynh´s Freebase Parallax. “This is only for experts!” is their response. But in a corporate setting, complex queries are part of our daily business – they are just not supported by common search engines (only exception being data mining solutions). But that doesn’t mean that we don’t need it.

Where is the way out of this dilemma?

• Don’t tell, but SHOW the end-users how semantic technologies can enhance search & browse experiences
• Do not use terms like SPARQL or RDF
• Create a simple mockup that illustrates the points you want to make
• You’re not a designer? Use tools like Balsamiq – Try it now!

Here is an example for a mockup of a semantically enhanced expert finder:

These kind of mockups are essential for any requirements engineering phase in any project where search is a bit more than a text box, a button and a bunch of documents.

It’s very perceptive of you to ask about the tasks that Parallax is presumed to address, and who the users are. I don’t have a specific answer beside “browsing graph of data more efficiently”.

I tend to think that contemporary graph-based data browsers either fly the user at 50,000 feet and show her the whole world in one window below (render a huge data graph as a huge visual graph), or leave her at the street level to wander around on foot (single resource view). I’m just wishing to provide her a car. Perhaps the good thing is that the car doesn’t come with a destination built in. (It’d be quite bad in real life if you need different cars to go grocery shopping and to go to work, for example.)

I quite like this metaphor he uses to describe the motivation behind Parallax, the UI prototype David designed as a novel way to browse Freebase data. It also ties in nicely with a wish made by Richard Cyganiak in an interview with him we published yesterday:

On the top of my wish list would be a really good data browser. The current crop of data browsers for RDF, such as Tabulator, Disco and the OpenLink browser, are still very basic and geeky. I hope for some sort of “Excel for Web data”, an application that allows me to browse through different datasets, find the bits that are relevant to my problem, and lets me slice and dice and correlate the data in different ways. I think such an app would be key to the kind of serendipitous reuse I mentioned earlier.

In the mailing list post cited above, David pointed to the Spellbound blog where Jeanne Kramer-Smyth published a showcase of faceted browsing across Olympics games facts using Freebase Parallax and suggested that Parallax would be particularly useful for exploring connected information:

Now take this idea to the world of archives and libraries, OPACs and finding aids and imagine the sorts of questions you can start asking. Yes – it does depend on the data being connected, but that is happening more and more all the time. The promise of the semantic web is structured data everywhere we turn.

Image bei Wiki Commons

In his screencast about this novel browsing interface, David stresses the advantages over Google or Wikipedia. Is this a fair competition? What is it about Parallax that makes it a choice interface and when?

1. If you want to learn a little more about Abraham Lincoln – go to Wikipedia!
2. If you want to know where you can find even more information about Abraham Lincoln – go to Google!
3. If you know a bit about Abraham Lincoln already, and you want to aggregate or compare some facts of his life to that of other presidents or if you want to visualise data on a time-line or on a map – learn how to use a tool like Parallax (and don’t complain if it isn’t as simple as Google anymore)!

In some respect, Parallax is the building block that has been missing in the web universe: (Professional) fact finding on the web could work like this in the close future (although Parallax needs some more servers and – indeed – more data in its database).

But what if Parallax became the graph-based UI on top of Freebase + LinkingOpenData?

Refined search results for “Shaka” on Parallax