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Challenging the Ideas Behind the Semantic Web
mytrip writes to tell us that after a recent presentation to the American Association for Artificial Intelligence (AAAI) Tim Berners-Lee was challenged by fellow Google exec Peter Norvig citing some of the many problems behind the Semantic Web. From the article: "'What I get a lot is: "Why are you against the Semantic Web?" I am not against the Semantic Web. But from Google's point of view, there are a few things you need to overcome, incompetence being the first,' Norvig said. Norvig clarified that it was not Berners-Lee or his group that he was referring to as incompetent, but the general user."
is the users.
Not the ones searching but the ones creating the content.
They'll be some idiot out there (like there is now) that will code his data in a way that guarantees that he gets the most page views etc. So often searched terms will turn up on search indexes and other ilk.
It's a loosing proposition unless you come up with filters but then they have their own set of problems.
There's a gorilla from Manilla whose a fella that stinks of vanilla and has salmonella.
"Norvig clarified that it was not Berners-Lee or his group that he was referring to as incompetent, but the general user."
Here I was, thinking we were arguing over Semantics...
Help save the critically endangered Blue Iguana
I'm calling the Anti-Neutrality Web Designers of Amerika!
Demands of inequality such as this should be allowed!
(btw, the spelling doctor has "loosing" as in "loosing the hownds for the huhnt")
But you just gotta have another sigarette
The current semantic web seems to offer a technology too fragile to use on the global scale. The complexity of various classification and ontological schemes, work needed to provide the metadata etc. Also, semantic web seems to offer great opporturnities for spammers and other mischief makers. Now we already have comment and reference spamming, but semantic web (on the global scale) raises the possibilities enormously.
The biggest problem with the semantic web is spam. If you can trust the tags, it's a beautiful idea. If you can't, it's worse than useless - it's a waste of time. Google has the right idea, automatic extraction of semantics from content. If there's no real content, then (hopefully) that will be reflected in the semantic analysis.
Me, I estimate we're 5-10 years away from doing anything terribly useful with all of this stuff, but I can definitely envision the day when an internet without semantics seems as distant as an internet without Google.
Thanks for the illustration of what Norvig meant. How is "Google Director of Search and AAAI Fellow Peter Norvig" (original article) semantically equivalent to "fellow Google exec" (Slashdot summary)? The latter suggests that Tim Berners-Lee too is a Google exec, which would be news to him.
What's a semete?
http://outcampaign.org/
Semantic webs (emphasis on plural) produced by editors such as those at /. or in the consumer-rated style of Digg, Del.icio.us etc might actually work. Trusting authors to do it right is a disaster, as Norvig suggests.
It's really, really difficult to get people to follow rules. We're lazy, we're incompetent (yes), and some of us are evil. I still don't think I truly understand how RDF is supposed to work exactly, and it doesn't even seem like it will be fun to try.
On the other hand, it's really easy to release a million monkeys and let the create what they will. It's not so easy to sort through what they end up producing, but Google does a surprisingly good job of this.
It reminds me of the early days of the Web, when companies like CompuServe and AOL wanted to design and own all content. On the other hand, an internet server with httpd let anybody make a ~/public_html directory and put up whatever they wanted to. The million monkeys won that battle. I think they'll win this one, too.
From http://www.7nights.com/asterisk/archive/2004/03/do nt-blame-the-users
Maybe the Semantic Web should aim to be useful to people rather than require people to be useful to it. There has to be a better way than trying to educate droves of people to a problematic and vulnerable design.
I design user interfaces for a free network management application,
In one of the very first papers mentioning the Semantic Web, some paragraph was devoted to something then lost in the hype around the semantic web: the Web of trust, which had to be something like a certification of metadata. This is perhaps to be again regarded as important for the semantic web and the web in general (although not easy to manage).
By the way, Norvig is not only a Google exec, but also a well known AI researcher, author of one of most important books on that subject.
Slightly offtopic. Peter Norvig gave a talk at my university on similar topics, and there was a short Q&A afterwards.
:)
One of the students asked him what he did for his 20% project. He said that he was usually too busy keeping tabs on what the other employees were doing with their 20% time, so he didn't quite get around to working on his. He told us what he wanted to do, as motivation for himself.
The basic idea is that when he used to work for NASA, it'd always make him upset when people saw faces in random spots on the moon's terrain, and claimed it was aliens that NASA was covering up, or similar. So, he was planning on taking facial recognition software and running it on all of google earth. I think it'd be pretty awesome..
Any progress yet, Mr. Norvig? I'd love to see the results..
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The jig is up!
I've been complaining about this and related issues for a while now. my last journal
Who would win? (/troll)
Do not mock my vision of impractical footwear
It's the business users too that are a problem. I'm currently trying to get a project on the rails based on semantic web technology, and I'm confronted with an IT department where some are even struggling with the difference between subtyping and instantiation- let alone more advanced modelling issues... It doesnt help ofcourse that most people never even heard of conceptual modelling languages such as ORM but instead were thought to use uml and ER where it's the modellers' responsibility to make a distinction between what is conceptual, logical and physical which ofcourse most never did.
In regards to the google issue I think the idea that you should crawl everything is faulty cause you need to be able to trust the source. Most ontologies will simply be restricted to a certain domain and corresponding user group, often in a b2b context. Integrating every man and his dog, the lawnmower and the kitchen sink with some kind of top level ontology is merely a nice-to-have philosophical issue that I dont expect to be solved in the near future, if only cause we havent seen much advances since Aristole started toying around with the idea. In other words, at google they are worried about an issue that's atleast a decade away from now, probably even more.
That anti-semantic bastard...
True, the web had a similar problem, however creating a webpage is a lot more interesting (you see the results directly, how terrible they might be you do see a result) than structuring data. The latter takes a lot more work, and the direct benefit just isn't there.
Sem-Web-like standards like RSS, XML and SOAP have become mainstream, but primarily because they fill a gap. The adoption of RDF or OWL simply doesn't solve anything. Yet. It would be cool to let agents loose onto the semantic web and retrieve them together with a summary on a certain subject using a multitude of sources, but as long as it's easier to Google I don't think it would generate any interest outside academia.
Feel free to prove me wrong though.
This sig is intentionally left blank
Exactly. Equally worse to the malicious content creator is the incompenent one.
As an analogy, look at FreeDB. It should be obvious that the CD information database loses much of its worth if entries are not double-checked for errors before submittal. Yet, there is so much crappy entries in FreeDB that it's just not funny anymore.
Ergo: Don't count on people to adequately tag or label content. It won't work.
Especially if the rules appear to be an incomprehensible ad-hoc mix of principles taken from a dozen not-quite-fully-baked AI dissertations.
I still don't think I truly understand how RDF is supposed to work...
I don't think anyone does.
I'm not saying that the semantic web is bullshit, but it does trigger my bullshit detector. At least one of them must be broken.
Am I part of the core demographic for Swedish Fish?
Even if we are inherently lazy, and even though some people seem to be generally against the idea, it doesn't make any sense to me not to employ this and experiment with it. Norvig is an AI guru, and his ideas on the Semantic Web may be interesting, but Google is not against the idea. Google's GData looks to me like a primitive Semantic Web. Even if only 10% of web masters adopt the system, querying to find a set of results that have been tagged as certain meta-data can come up with some interesting results. If the results are interesting enough, more webpages will include meta data tags. Also, being inherently lazy argues for not spending time writing tags all over your code, so why would anyone take the time to sabotage the system. While I understand the difficulties of the spamming problem, there are plenty of cookies on the internet anyway. I think the same inherent problem in the Semantic Web exists with PageRank. In PageRank what happens is a web page will say the same words over and over to acheive a higher ranking in the semantic analysis of the page, and thus the page will be a top result when entering a query with related words. But I think PageRank works pretty well overall. Google's next step with PageRank is to filter all the spam sites that just say the same words. Security in the Semantic Web would also be to filter those sites with obviously spammy RDF or OWL tagging. Overall the Semantic Web is a cool project that could lead to really smart searches, with axioms involving how different meta-tags are related to each other. I'm in favor of the new technology.
The idea of RDF is applicable to much more than public innerweb content. I've spent the last 7 months researching and developing an RDF backed system for my company's core products. Everyone should think of the value of RDF beyond the scope of trust, and then it becomes easy to realise methods of simple non-web implementation. We can all spend the next 5 years pondering how we're going to figure trusted content providers for RDF web data, or we can just start developing apps for sources which understand themselves as trusted (ie. data input from an individual, employees of a company, and any group where the individual must be accountable for their actions). Whats more important than the blind trust of sources, is data verfication. There are ways to run data input from one user by another user, without doing it in an infringing, demanding way, for validation. I'd like to go into detail of exactly what I mean by all this, but I don't want to violate any portion of my NDA or tip off industry competition (I know that sounds retarded, sorry). If RDF does gain popularity, I can say it will from within the private sector, not the public. Genious implementation may bring RDF to the public sector, but thats not something I would say is guaranteed to happen.
Current technical obstacles to creating any RDF applcation: The matter of complexity of its integration into DB backed systems (popular methods), and instatiated class marshaling within not-so-object oriented languages. The technical design and implementation of a standards compliant RDF system has been extremely difficult for me. I don't think it would ever be possible to get RDF data represented nearly as minimally as you could with simple relational tables (although formally no more bloated than bloaty XML). RDF also creates many long linked relationships; this tends to create some serious performance issues in querying the data. Lastly, I hate XML, and you can't always correctly export from RDF to XML (capable type to incapable type) in a correct manner.
This remind me of the famous Semantic knigth parody...
Do not forget that the semantic Web is not a replacement of the existing technologies: HTML contents will always be there but, What if these little 'metadata' description where added to ALL the Web Pages? In this case, the pages could be categorized, analysed and searched much more easily, and the algorithms related to these operations would be better. In such an scenario, the use or one or another Web search engine would be irrelevant because all of them would have powerful and acurate algorithms. Maybe a threat to google's business model? These would be the perfect world, but we have to assume that Webs would certainly lie or made mistakes in their semantic descriptions. OK, but... would it produce an scenario worst than the actual?. Now, fake webs are quite common; irrelevant sites try to advertise them by using all the available means to attract the most visitors, misleading them. The best web search engine is this who best filters these sites in the searches. In a semantically described Web, the problem will be the same, but there would be another easy-to-use filtering criteria to enhance the results. the Web search engines' algorithm will be better for sure.
Bah, semantics...
<before>now</before>
There is no way that regular people, even the majority of intelligent educated people, are going to be able to use it. It's a ridiculous pipe-dream. Think how hard it is to get people to understand broken-down logical arguments where everything is already layed down for them, and now imagine trying to make them understand how to conceputalise their own data domains and define their own relationships. Maybe 2% of people could do it properly, and then 1% of those would end up in a profession that would use the skills.
When programmers write software for general use we have to think how to make things easy multiple levels below the level we have to think at. The vast majority of people are not able to think technically, and do not have patience - and that's because most people in this world find it uncomfortable to do anything that isn't centred around a social or emotional act.
Developers find users can't do programming, so the programming language becomes a graphical interface. The users can't navigate the graphical interface via a structure based on logic, so the screens get built into an icon based organisaion with a well-defined 'workflow'. The user can't think logically about how to use the graphical interface, so help is written to explain how it works and what it can do. The help is too general so specific examples are given. There are too many examples and the user can't be bothered to read them, so a colleague stands next to them and they learn to mimmick their colleague.
This isn't an extreme situation - it is typical of the vast majority of users. Now think about the inherent technical complexities of OWL and RDF, and imagine people actually using it for real problems? There's no way to hide what is a purely logical and structural framework for organising extensive data, behind pretty pictures and simple examples.
Brilliant! Blame the user. No, it's not that you don't have a rational data model (you know, so that those "semantic" tags actually *mean* something) or that you haven't done squat to even suggest a proper UI, it's the user's fault.
And it *certainly* couldn't be that HTML is a piece of fucking garbage and that trying to kludge semantics into the spec is an effort doomed from the beginning.
Bingo! You've just proven that the incompetence spreads beyond MySpace.
The problem with the semantic web movement is this: You have the web guys from the W3C who got famous by building kinda crappy, but effective technology (HTTP, HTML, etc...) going goo goo gah gah over PhD Ontologists from the AI community. They team up and build these great things that the average person (including the people who think they are really really smart, like the Slashdot editors), has no chance in hell of using effectively. What'll happen, is that eventually there will be useful Semantic content and Intelligent Agents doing great things, but that work will be done by a select few. The unwashed masses will still be the domain of Google.
Help me take back Slashdot. When did 'News for Nerds' become 'FUD and Conspiracy Theories for Extremist Nutjobs'?
I don't understand why the semantic web has to start of so complicated.
Learn from RSS, which is relatively simple, and got adopted quite fast.
For example: let's say everyone puts a robots.rdf file in the root of their website, which contains some very simple things, a vcard with address info, telephone numbers, gps coordinates and opening hours (if it is bussiness). That would be such a great addition for the web.
Let's first try to create the equivalent off the yellow pages. Where you can look up some info in a simple structured manner, instead of wading through webpages with impossible designs.
Google will always be necessary for 'fuzzy' text searches, but if we could put the simple facts in more structured/simple documents, it would help sooo much. I don't really understand why the people in google don't try to push this kind of technology. Maybe because everyone can write a spider for these documents, so it's not that interesting for them, just like (in my view) they never really embraced rss.
Jasp
The context will tell you if you have usability problems or not.
If an important group of users is grandmothers, trained or otherwise, and they can't use your product or service (call it F22 or a kettle) then you have got usability problems and you have got to address them.
Insulting the intelligence of your intended audience is a typical no-no for somebody knowledgeable with the rudiments of usability theory and practice.
IANAL but write like a drunk one.
So instead of insulting a very small amount of people, he insults everybody in the world...
Way to go!
News at 11...
Joachim
People don't write Manifestos any more -- what's going on in this world? [Frank Zappa]
As I pointed out in the previous comment authoring data on the semantic web is no more difficult than authoring RSS or XML.
Yes, figuring out for the first time how to represent your data in RDF (or XML for that matter) can be difficult. Imagine if everyone was trying to come up with an RSS standard on his own instead of using RSS export functionality of his content management tool. That's why we need good guidelines how to publish information on the semantic web. And RDF export functionality (plugins) similar to what RSS plugins are doing.
As for opportunities for spammers and mischief - don't think so.
Why? - If you look at the Semantic Web "layer cake" you will notice such technologies as digital signatures, encryption and trust being part of the scheme. They allow to identify the author of data and ensure he is what he claims to be. There is nothing wrong with your application if it only accepts signed and trusted data. And there is nothing preventing authors of the data from signing the contents. Since the semantic web is a new technology and we already know about problems that spam and misuse can present it is more not less prepared to fight spam.
Note1: Semantic web should be viewed as an integral part of the existing web, not its opposite. Might even be that it can provide an additional layer that will help to combat spam and other problems you mention here. Who knows.
Note2: Spammers will always try to come up with new exploits. We all have to be prepared for this and think how to close the holes they are using. But saying that newer (a further development of existing [web]) is necessarily more opportunities for spammers in wrong.
Here is a Tutorial on the Semantic Web.
Pay attention to the slide #22 which shows how data from different sources can be merged together. This is one of key differences between XML and RDF - to merge XML data from a number of different schemas one would need to create an application that processes data in these schemas and generate merged data (possibly inventing a new schema to represent the merged information).
In RDF that happens "magically" - in order to merge heterogenous data you don't need to do *anything* - just put all the information in an RDF store and it merges. If the data to be merged change no modifications to the store are necessary - it is like a bag that can hold anything.
A good point about the million monkeys. :)
;)
To illustrate one of key differences of how RDF is supposed to work and why it may even be fun (and not to post same info again) check out at this comment: Tutorial on the Semantic Web.
A simple and concrete example: when a conference publishes its delegate list in RDF it is suddenly very easy for services that use this data to appear. By combining this data with Google Maps we get a FOAFMap of its participants where the application has extracted machine readable data from RDF, used geo-information to put them on the map and has retrieved more data from FOAF RDF profiles of the participants.
That's a simple mashup, but it shows how machine readable data can help spring new and sometimes unexpected use cases. I don't understand why all conferences do not provide data in RDF yet.
Although trust is certainly a issue when it comes to the Semantic Web, the real problem is that its design is not a true abstraction, but is nothing more than more metadata. And like the actual textual data in a typical web page, it suffers from all the same problems, save for one: being unstructured (and thus not truly parseable).
IMHO, the Semantic Web is solving one problem (the lack of structure and descriptive context in textual HTML content) in a very hard way (asking the entire web to implement this new RDF).
Many companies (disclaimer: like my own) are approaching these problems from a different angle: working on statistical and semantic systems to extract structurue from the textual content that is already there on the web page.
Now some people will argue that trying to create a system that can understand langauge/content is insanely difficult.
But what is a more realistic time frame? The one in which an intelligent parser can begin to understand the content that is already on the web, or the one which requires the entire world to implement a solution to a problem they don't even realize is a problem?
But what, exactly, is the definition of the 'Semantic Web'? How is it different from what has been done in the past? Is there any agreement of any sort as to what it means? If yes, please let me know. If not, then how can we achieve this goal if we do not know what it is?
I am confused, I really do not see too many differences in the web in the last few years. Nothing 'Earth Shattering' anyway.
putting the 'B' in LGBTQ+
"The idea of RDF is applicable to much more than public innerweb content. I've spent the last 7 months researching and developing an RDF backed system for my company's core products."
You've resolved the trust issue by limiting it's domain. e.g. intranet.* BTW there are ways of getting semantics from content that are "clever".e.g. making it a game.
*The advogato trust metric may be a way of resolving the issue.
The same chasm appeared during the founders panel, where John McCarthy gave a more sober cautious perspective of where AI is going, while Marvin Minsky issued a call for the old style of over-hyped research such as the "emotion machine" whatever that means.
There was also a feeling that perhaps some of the grand challenges are too ambitious. "We can't make predictions since in some cases we don't even know what the problems are" a famous panelist noted. It is good to have long term goals, but they must be set within the realm of what is at least vaguely foreseeable. Challenges beyond that boundary are in the realm of science fiction not scientific AI.
"What's a semete?"
It's what you inpregnate computers with.
Google to Berners-Lee: you are PWN3D!
Given the track record of Good Old-Fashioned AI in building something genuinely useful, I'm afraid Semantic content and Intelligent Agents will not be involved in great things for a while. Maybe in 50 years ;)
That last one means that straightforward, guaranteed-to-reason-correctly searchers for semantic webs won't scale, which means their use on the global internet is problematic. Failure to scale was one of the major causes of AI winter, guys.
To a Lisp hacker, XML is S-expressions in drag.
It's trying to impose structure on something that is not very structured--human thought. Even the use of the word "semantic" points out the futility of the exercise, as it indicates language and changes in meaning--not structure.
Semantics is a human discipline--it is focused inward, not outward. Likewise the proper place for semantic technology is in the client, not the content. Building "semantic web sites" makes no sense. Google is absolutely right on this one--Web sites should simply be what they are, and it is up to the client to assign meaning and remember connections. Google provides a variety of tools that help people do just that.
Why should I have to tag everything I read online? I don't tag things I see in real life. I just remember them and make connections in my mind. If we want computers to be actually useful to us as assistants and not just stupid tools then they will need to begin to operate the same way. That is a very tough problem, yes. But it is the way we are headed, and the "semantic web" is IMO just a bad hack until we get there.
Furthermore the idea of trustworthyness and authority online is ridiculously complicated. I can't think of a harder problem in all of AI. It's much harder to determine if someone knows what they're talking about, or if they are trustworthy, than it is to simply identify the topic of an article. And we're still struggling with the latter.
Build a man a fire, he's warm for one night. Set him on fire, and he's warm for the rest of his life.
"You can't fix stupid"
;). That's right, go with that thought. Web 2.0 is garrrrrrbage.
--Ron White.
Seriously though, web 2.0 is going to have a hard time with thousands of arrogant programmers making claims that it is crap because they can't figure it out. So maybe it will be a niche market
The basic problem with the SW is that the use of separate ontologies defies any exchange process that does not include human intelligence. IOW to do it properly there must be human intervention. But Berners-Lee keeps thinking that there is a shortcut - there isn't. Better men have trod this path and know what's at the end of the road.
Fellow moderators, parent is the most Insightful comment I've seen in this thread; the Semantic Web is all about human-provided content represented in a common format, just like Web 1.0 was!
Someone with points please mod it up!
Singularity: a belief in the "God" idea with the "demiurge" relation inverted.
This stalking thing's hard work. I'm glad I could track you down to ask: I'm interested in downloading your software, where might I find a link to it?
The SW doesn't work and won't work. Give it up. The real future is in the nouvelle AI as demonstrated by Luc Steels' research, wherein negotiation of language and negotiation in language in a real-world environment establishes the semantics of communication.
If we want to get users to enter in metadata, we need to do three main things:
- create editors that automate the syntactical complexities of RDF/OWL, like what blogs have done for HTML.
- make entering metadata entertaining somehow.
- make some killer apps that show to regular users the usefulness of the semantic web.
Then we'll have a semantic web. Problems like spam can just be addressed as we come to them, but Web of Trust is probably a good start.
random underscore blankspace at ya know hoo dot comedy.
Specifically, to get these technologies adopted in a business environment, somebody has to be able to explain to executives what the benefits are and the cost, and therefore why they should adopt this technology, and if it's for sale somehow, why they should invest in semantically aware software/hardware. The barrier here is that business guys who write checks may not be technical, or not very, and sales guys who talk to them are also not generally technical. So it doesn't get traction because the benefits are hard to explain and the stuff you do to get the benefits is really inscrutable. There are a few areas where SW is getting significant adoption (pharamaceutical research is one) but in general it is off the radar screen and the vendors providing software that implements this stuff are niche players.
Just click on my SlashDot username (directly above) and read my posts attached to "Robot Dogs Evolve Their Own Language". There you'll find links to Steels' work. Google him, too.
All I would ask of the Semantic Web evangelists is that they go off together and build a network of Semantic Web systems that proves the following: 1. It works 2. It is more useful than currently existing practices 3. It is more cost-effective than currently existing practices 4. There is a killer application that is not possible using currently existing practices If they can do #1 and any one of the other 3, then maybe people will see the value and start adopting it in the real world. Until then Semantic Web sounds like the Dvorak keyboard to me: a "solution" that everbody thinks is worse than the problem it is trying to solve, because it requires millions of people to change the way they do things without much proven benefit. What Semantic Web needs to do is prove is that it is actually worth implementing by showing some honest results.
Do I hear a Googlefight in the making? Why yes, it's Norvig vs. Berners-Lee.
Google seemed to be looking to the web for meaning, but they should be building their own Ontology of Everything, based on what they find in the content. Let Cyc loose on there caches perhaps would be a good start. Then integrate their Ontology of Everything with those Formal Ontologies that already exist. About Intelligent Searching, when a person asks me for advice, I tap into my Personal Ontology, which has overlap with other ontologies in a domain specific way. i.e. I read information, much of it structured, I then fit it into my Personal Ontology and if required expand my ontology to fit the new information. I may even face a paradigm shift that requires a major restructuring of my Ontology, i.e. I need to have a set of new transforms to link the old with the new in a way that lets me sanely access both. At this point I have acquire new Knowledge which I can now share with people that ask me questions. When I'm talking to a Knowledgeable Source I need to find the Transforms that allow me to incorporate "knowledge of shared knowledge" as well as knowledge of our unique knowledge. This is how we are able to communicate and learn from each other. If I am dealing with a Naive Searcher I need to Probe their Personal Ontology or World View until I am able to construct enough domain specific transforms to allow me to know what they are trying to learn and how best to find it and Teach it to them.
I totally agree with Peter Norvig.
l og.html
:- adoptedBy(X, Y). :- fatherOf(X, Y). :- motherOf(X, Y).
;-)
There has been a lot of enthusiasts but also a bunch of stumbling amateurs in AI all around the Semantic Web project, and this has not been a good thing.
They are reinventing the wheel. RDF is nothing more than knowledge representation 101.
Don't forget that Russell & Norvig's book devotes 5 out of its 26 chapters on KR.
And now with the DAML language they are reinventing Prolog interpreters.
From their Website - Why use DAML?
http://www.daml.org/2002/04/why.html
(motherOf subProperty parentOf)
(Mary motherOf Bill)
when stated in DAML, allows you to conclude
(Mary parentOf Bill)
Check this from an introductory course in Prolog
http://www.cs.wisc.edu/~noto/cs540/lecture/14-pro
fatherOf(keith, duane).
motherOf(keith, diana).
adoptedBy(webster, mrPapadapolis).
parentOf(X, Y)
parentOf(X, Y)
parentOf(X, Y)
Given a query, parentOf(keith, X)., Prolog will:
?- parentOf(keith, X).
X = duane ;
X = diana ;
LOL
I see, maybe two real innovations : URI (Uniform Resource Identifier) and Digital Signatures and Web of Trusts.