Ask HN: What happened to the semantic web? • Hacker News Board

Re: Ask HN: What happened to the semantic web?

#51

Post by ssfrr » Wed, Apr 11, 2018, 2:06 PM UTC

pornel wrote: post #34

1. We've realized that people in general can't reliably and consistently mark data up. That's a problem of incentives, technical difficulties, UI, bitrot of invisible metadata, etc. 2. We've settled on extracting information from "raw" text (with everything from regexes to recognize flight info in e-mails to getting word statistics from terabytes of garbage) and duct-taping that with special-purpose APIs.

The flight info example is one of the places where semantic web tech went mainstream. Those flight emails have embedded metadata in JSON-LD (linked data) format and Gmail uses it for more specialized display[1].

[1]: https://developers.google.com/gmail/markup/reference/flight-...

Re: Ask HN: What happened to the semantic web?

#52

Post by crazysmoove » Wed, Apr 11, 2018, 2:09 PM UTC

crazysmoove wrote: post #21

One of the big things to come out of the semantic web was RFD-A (embedding semantics in unstructured web pages) and similar technologies (microformats, JSON-LD, schema.org). It's what lets Google show product reviews and rankings in search results, and lets shopping aggregator sites show things like price comparisons from other websites. While it's probably not as widespread as its boosters from a decade ago hoped it…

Sorry, that should be "RDF-A," not "RFD-A."

Re: Ask HN: What happened to the semantic web?

#53

Post by ghaff » Wed, Apr 11, 2018, 2:22 PM UTC

kristianc wrote: post #50

ghaff wrote: post #33

It was the sort of largely academic tops-down exercise to organizing information that has mostly lost out time and time again to more organic bottoms-up/self-organizing approaches. Think Yahoo vs. Google. [ADDED: i.e. manually populating hierarchies vs. search, in case that wasn't clear] I remember when it was going to be Web 3.0. Tim Berners-Lee gave a talk about it when he won the Draper prize. As others have said,…

I think there's a lot in this. The first users of the Internet saw themselves as librarians and curators, and sought to impose that vision of the world on everyone else. For a long time, people had trouble with the idea that everything didn't need to link to everything else.

Hierarchical structures are how we organized things historically. So I think it's pretty natural. I know that for a long time I was relatively careful about filing email, files, etc. into a folder hierarchy and categorizing my music collection. I won't say folders (and tags/labels) don't still have their uses. But I've definitely moved away from spending so much upfront time to carefully organizing stuff that I may want to find some tiny percentage of some day. Instead I mostly figure I can search for it if I need to.

Re: Ask HN: What happened to the semantic web?

#54

Post by jerven » Wed, Apr 11, 2018, 2:22 PM UTC

It became useful for people who have as job using public data or providing it. Such as the life sciences, governments and the archaeology/history and more. It allows for nice bottom up standards and user interfaces such as flight data in your e-mail.

If your not consuming a lot of public data or providing data to the public it is not very useful other than having a bunch of better graph databases associated with it.

Re: Ask HN: What happened to the semantic web?

#55

Post by tastyham » Wed, Apr 11, 2018, 2:24 PM UTC

It was a stupid idea, although remnants can be seen in html5 with elements like address and , nav, and section.

Turns out that keeping presentation and data separate is much, much easier. Hopefully HTML 6 will get rid of everything except for div, span, and form elements.

Re: Ask HN: What happened to the semantic web?

#56

Post by NelsonMinar » Wed, Apr 11, 2018, 2:35 PM UTC

Google got good enough at divining the content and meaning of a page without needing magical XML pixie dust to annotate the facts on it.

Re: Ask HN: What happened to the semantic web?

#57

Post by TeMPOraL » Wed, Apr 11, 2018, 2:48 PM UTC

naasking wrote: post #31

drcode wrote: post #25

I think the main issue is that even though "knowledge representation" with ontologies is an enticing goal, it's simply a fact that real entities, as used by humans at a practical level, don't map neatly onto mathematically-sound hierarchies.. . To see this, just look at the arguments the ancient Greeks already had as to whether a human is a "two-legged featherless animal" or the endless online arguments as to whether…

> don't map neatly onto mathematically-sound hierarchies. I think they do, but finding the right mathematical model is very difficult. If it were easy, everyone would be a mathematics PhD. Learning to program is becoming efficient at recognizing the right spherical cow in any given situation, because such shortcuts are essential to getting shit done.

I disagree. It all boils down to the way we use language - words have meanings, but those meanings are just pretty fuzzy boundaries in conceptspace. It seems that words represent concrete things from a distance, but if you look closely, it all breaks down. Hell, the meaning of words also heavily depends on context in communication, so they can paint barely overlapping borders in conceptspace from one conversation to another.

Programming is actually great for discovering this. Especially OOP, with its introductory examples of animal taxonomy and shapes.

Re: Ask HN: What happened to the semantic web?

#58

Post by rspeer » Wed, Apr 11, 2018, 2:59 PM UTC

smadge wrote: post #17

rspeer wrote: post #12

Earlier quoted context omitted.

The Semantic Web as originally imagined is also incompatible with privacy, and with malicious fake data. So is the decentralized Web you imagine, I think. Let's keep using FOAF as an example. The facts about who knows who in FOAF are just bare RDF triples. There's nothing about who's allowed to know who knows who. There isn't even room to specify who's allowed to know who knows who. If any significant number of peopl…

First, Does it matter much if agents spread misinformation in an unstructured versus structured format? I can already assert that I am married to Tim Berners-Lee. I will do so right now: I am married to Tim Berners-Lee. I will do so again: "smadge" . "http://example.com/timbl" . . I think the maxim "not everything on the internet is true" applies to linked data just as much as unstructured data. Second, although agai…

Reification is at least part of the solution to provenance, but none of the Semantic Web ontologies you've ever heard of use reification, and there is no upgrade path to make an ontology based on plain un-reified triples use reification.

To continue this example: you asserted, in English, "I am married to Tim Berners-Lee". In English, anyone can respond "No you're not".

Then you said it again in RDF, in a way that hypothetically a computer system would use to draw conclusions. And there is no way to say "no you're not" in RDF.

Re: Ask HN: What happened to the semantic web?

#59

Post by drcode » Wed, Apr 11, 2018, 3:02 PM UTC

icebraining wrote: post #29

drcode wrote: post #25

I think the main issue is that even though "knowledge representation" with ontologies is an enticing goal, it's simply a fact that real entities, as used by humans at a practical level, don't map neatly onto mathematically-sound hierarchies.. . To see this, just look at the arguments the ancient Greeks already had as to whether a human is a "two-legged featherless animal" or the endless online arguments as to whether…

But RDF was pretty good with that, because it didn't force records into hierarchies. You could just define relationships, and then create them freely between records. Some people created heavy ontologies, but it wasn't a result of the data model.

Right, but the whole dream of the "semantic web" to me was that one website could discuss red wines, and another website could discuss Vietnamese food, and then a reader could use the semantic vocabulary shared between the two sites to arbitrarily ask questions such as "what wine will go best with this dish?"

If you just have a vocabulary where everyone can freely define concepts and their relationships in a fuzzy way this original goal will never be tractable- There needs to be some sort of unambiguous shared concept space between disparate sites (which in my estimation appears to not be achievable in any practical sense, due to the difficulty in finding "one true way" to build ontologies.)

Re: Ask HN: What happened to the semantic web?

#60

Post by drcode » Wed, Apr 11, 2018, 3:05 PM UTC

naasking wrote: post #31

drcode wrote: post #25

I think the main issue is that even though "knowledge representation" with ontologies is an enticing goal, it's simply a fact that real entities, as used by humans at a practical level, don't map neatly onto mathematically-sound hierarchies.. . To see this, just look at the arguments the ancient Greeks already had as to whether a human is a "two-legged featherless animal" or the endless online arguments as to whether…

> don't map neatly onto mathematically-sound hierarchies. I think they do, but finding the right mathematical model is very difficult. If it were easy, everyone would be a mathematics PhD. Learning to program is becoming efficient at recognizing the right spherical cow in any given situation, because such shortcuts are essential to getting shit done.

I think you'd change your tune (like I did) once you dig into the ugly details of such mathematical modeling. A book like this will show you just how hard this is https://www.amazon.com/Knowledge-Representation-Reasoning-Ar...