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A Review of the Semantic Web Field

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Re: A Review of the Semantic Web Field

#51

Post by namedgraph »

j-pb wrote: post #17
cheph wrote: post #14

Earlier quoted context omitted.

> CURIEs and the depending standards alone are well over 100 pages. The curie standard is 10 pages long, and those "dependent standards" includes things like RFC 3986 (Uniform Resource Identifiers (URI): Generic Syntax) and RFC 3987 (Internationalized Resource Identifiers (IRI)) - which are well established technologies that most people should be familiar with. And you really don't need to read all of the referenced…

Familiarity isn't nearly enough if you want to implement something. Talking about RDF is absolutely meaningless without talking about Serialisation (and that includes ...URGH.. XML serialisation), XML Schema data-types, localisations, skolemisation, and the ongoing blank-node war. The semantic web ecosystem is the prime example of "the devils in the detail". Of course you can explain to somebody who knows what a grap…

RDF is absolutely about triples and the converse graph form! The serialization formats are immaterial, orthogonal. The fact that you think it's about any particular format makes it obvious that you don't get it at all.

Re: A Review of the Semantic Web Field

#52

Post by j-pb »

namedgraph wrote: post #51
j-pb wrote: post #17

Earlier quoted context omitted.

Familiarity isn't nearly enough if you want to implement something. Talking about RDF is absolutely meaningless without talking about Serialisation (and that includes ...URGH.. XML serialisation), XML Schema data-types, localisations, skolemisation, and the ongoing blank-node war. The semantic web ecosystem is the prime example of "the devils in the detail". Of course you can explain to somebody who knows what a grap…

RDF is absolutely about triples and the converse graph form! The serialization formats are immaterial, orthogonal. The fact that you think it's about any particular format makes it obvious that you don't get it at all.

The fact that you think you can use RDF without implementing ANY format, makes it obvious you don't get it at all.

Specifications are nice and cozy until you hit the harsh reality of implementing them.

"RDF iS oNlY tHe abStrACt GrApH StrUCtuRe", please, spare me the marketing bullsh*.

Re: A Review of the Semantic Web Field

#53

Post by JPKab »

LukeEF wrote: post #11

We built a new semantic database first in university and then commercial open source (TerminusDB). We use the web ontology language (OWL) as a schema language, but made two important - practical - modifications: 1) we dispense with the open world interpretation; and 2) insist on the unique name assumption. This provides us with a rich modelling language which delivers constraints on the shapes in the graph. Additiona…

I was "stuck" working with a bunch of leading academics and researchers on a SemWeb project using OWL/RDF, in collaboration with DARPA and the US Department of Defense, around 2008-2009.

You are absolutely correct that they are hostile to anything outside of their "ideology".

The awful, horrific performance of the RDF/OWL databases compared to the impure, heretical evil Neo4j that they despised for its practicality..... that was always funny.

Another interesting thing I encountered in the field was the side-effect of an academic field that sounds really good to people who have never built anything EVER is that it can often get a ton of funding and grant money from central government organizations, thereby creating legions of rather shitty companies (especially in the EU, where the grants were everywhere) that have the word "semantic" in the name even though they do nothing with actual semantic technology. These shitty companies are often just there to employ the academics.

The craziest thing was these projects where they would employ a dozen or so "library scientists" who were all just masters and phd students who had, for some reason, decided to study to be librarians in the digital era to create the OWL ontologies. None of them knew anything about computer science or programming, and they would just sit there and read thousands of policy documents and use an Eclipse based GUI to create and edit giant graphs of knowledge and rules. All were being paid six figures, and didn't produce a single goddammed thing of value. So much taxpayer money in those rooms going to complete waste. Glad it wasn't just me that thought the community was a joke.

The semantic web will arrive one day, but OWL and SPARQL won't be anywhere in it. And it won't be any of these academics delivering it.

Re: A Review of the Semantic Web Field

#54

Post by JPKab »

tannhaeuser wrote: post #15
LukeEF wrote: post #11

We built a new semantic database first in university and then commercial open source (TerminusDB). We use the web ontology language (OWL) as a schema language, but made two important - practical - modifications: 1) we dispense with the open world interpretation; and 2) insist on the unique name assumption. This provides us with a rich modelling language which delivers constraints on the shapes in the graph. Additiona…

You're right to emancipate from the grab that SemWeb has had on the field for so long and turn to Prolog/Datalog and practical approaches IMO. Open world semantics and sophisticated theories may have been a vision for the semantic web of heterogenous data, but in reality RDF and co are only used in certain closed-world niches IME. Pascal Hitzler is one of the more prolific authors (especially with the EU-funded ident…

I met Pascal Hitzler on a few occasions, not long after he ended up relocating from Germany to Ohio to work at Wright State. He was a rare bright spot in always trying to bridge the gap between theory and application in the SemWeb community. He was kind enough to meet up with me and a colleague at a coffee shop in Dayton to discuss our project, all pro-bono. A real good dude.

Re: A Review of the Semantic Web Field

#55

Post by saltcured »

namedgraph wrote: post #45
jerf wrote: post #32

Earlier quoted context omitted.

"Our feeling on interacting with the semantic web community is that innovation - especially when it conflicts with core ideology - is not welcome." I wasn't a big fan of the "semantic web" community when it first came out, and the years have only deepened my disrespect, if not outright contempt. The entire argument was "Semantic web will do this and that and the other thing!" "OK, how exactly will it accomplish this?…

It's not what you have to do, or how, it's that for the first time we have a common model for data interchange (RDF) with which you can model concepts and things in your domain, or more-importantly across domains, and simply merge the datasets. Try that with the relational model or JSON. Integration is the main value proposal of RDF today, nobody sane is trying to build a single global ontology of the world . You can…

Many of us who have been in these battles over the decades have decided that the interchange format is almost irrelevant to the real challenge which is the modeling and semantic alignment. It's a useless parlour trick to merge graphs and call them integrated, approximately as it is to put several CSV files into an archive or simply loading unrelated tables into one RDBMS. Yes, you can run a processing engine on the amalgamation, but all the work remains to do in establishing a federating model within your query or processing instructions.

Over and over, we see that the real world problem is gated on human effort to negotiate about the models and to do data cleaning and transformation. And, the best results almost always require that modeling, cleaning, and transformation be done with an eye towards a specific downstream consumer or analysis. We get tired of having to steer leadership back to reality after they buy into the snake oil suggestion that integration costs can be avoided and unknown applications solved.

The claim that RDF solves federation more than any other serialization format for structured data and models is about the same as fixating on JSON versus XML or YAML or Lisp s-expressions.

Re: A Review of the Semantic Web Field

#56

Post by j-pb »

namedgraph wrote: post #50
j-pb wrote: post #5

Earlier quoted context omitted.

I think that's a symptom, not the cause. The complexity of web standards in general smother it with it's own weight. The common web has enough raw financial and person backing to grind through that. The semantic web does not. CURIEs and the depending standards alone are well over 100 pages. Language tags alone has 90. RDF has like 100, Sparql has a combined of more than 300, and OWL has more than 500, even though it…

OWLAPI, Protege - that's it? RDF libraries broken? Dude what rock are you living under? What about Jena, RDF4J, rdflib, redland, dotNetRDF etc? Most of these libraries have been developed and tested for 20+ years and are active. See for yourself: https://github.com/semantalytics/awesome-semantic-web#progra... Why are you spreading FUD?

Jena is everything but user friendly, it has a lot of weird edge cases, bugs, and a horrible API.

RDF4J is okay for RDF, but completely ignores OWL.

RDFLib is a bug ridden mess, have you ever used it, or checked their issue tracker, and commit history? With that amount of production breaking bugs that haven't been resolved for years, it might as well be unmaintained.

Redland has last been updated years ago. Sure there's software that's finished, but with the complexity of RDF, OWL and friends, my hypothesis would be "it's dead Jim".

I haven't used dotNetRDF, but it looks okay at first glance. So at least you can do semantic web on windows...

YES! THEY'VE BEEN TESTED FOR 20+ YEARS AND ARE STILL HALVE BAKED, BUG RIDDEN, REASEARCH PROJECTS. MY POINT EXACTLY. These are all smart, dedicated people. The semantic web ecosystem is too complex to get right, no matter how many hours and $$$ you throw at it.

I have nothing to gain from talking about the shortcomings of RDF and it's related standards, except maybe inspire people to come up with something better, and to save themselves some pain and suffering.

The pot calling the cattle black. Your motives seem more questionable, with the whole "username matches the topic talked about", and has a Semantic Web consultancy business, shtick.

Re: A Review of the Semantic Web Field

#57

Post by wuschel »

lou1306 wrote: post #40
wuschel wrote: post #27

Earlier quoted context omitted.

> [...] but we must extract the good and remove ideological barriers to participation. Could you point to some resources that explain the tradeoff between the practical solutions and concepts and the ideologic cruft for an outsider?

Not the commenter, but I hope to add something to the discussion. Generally, expanding on the current state of the art is paramount in academia. In this case, I guess that defaulting on closed-world and unique names is frowned upon because academic people "know" that SemWeb concepts would be "easy" to implement under such conditions (for some interpretation of "know" and "easy"). A university lab would be reluctant t…

Very interesting. Thanks!

Re: A Review of the Semantic Web Field

#58

Post by namedgraph »

saltcured wrote: post #55
namedgraph wrote: post #45

Earlier quoted context omitted.

It's not what you have to do, or how, it's that for the first time we have a common model for data interchange (RDF) with which you can model concepts and things in your domain, or more-importantly across domains, and simply merge the datasets. Try that with the relational model or JSON. Integration is the main value proposal of RDF today, nobody sane is trying to build a single global ontology of the world . You can…

Many of us who have been in these battles over the decades have decided that the interchange format is almost irrelevant to the real challenge which is the modeling and semantic alignment. It's a useless parlour trick to merge graphs and call them integrated, approximately as it is to put several CSV files into an archive or simply loading unrelated tables into one RDBMS. Yes, you can run a processing engine on the a…

Relational model, XML/JSON etc. simply do not have a generic merge operation defined the same way as RDF does. This can be proved with pen and paper.

And you still haven't addressed my second point about widespread industry use. It seems that SemWeb haters/sceptics always try to avoid this, why could that be?..

Re: A Review of the Semantic Web Field

#59

Post by namedgraph »

j-pb wrote: post #56
namedgraph wrote: post #50

Earlier quoted context omitted.

OWLAPI, Protege - that's it? RDF libraries broken? Dude what rock are you living under? What about Jena, RDF4J, rdflib, redland, dotNetRDF etc? Most of these libraries have been developed and tested for 20+ years and are active. See for yourself: https://github.com/semantalytics/awesome-semantic-web#progra... Why are you spreading FUD?

Jena is everything but user friendly, it has a lot of weird edge cases, bugs, and a horrible API. RDF4J is okay for RDF, but completely ignores OWL. RDFLib is a bug ridden mess, have you ever used it, or checked their issue tracker, and commit history? With that amount of production breaking bugs that haven't been resolved for years, it might as well be unmaintained. Redland has last been updated years ago. Sure ther…

Research projects? Research is something coming out of academia, as you know. These are open-source projects with active developer communities. Jena has long been under Apache, RDF4J is now under Eclipse Foundation.

Can you for once answer why large companies in the industry are using RDF/SPARQL as of today if it's so "dead"? Here's a list: http://sparql.club

Re: A Review of the Semantic Web Field

#60

Post by ta988 »

JPKab wrote: post #53
LukeEF wrote: post #11

We built a new semantic database first in university and then commercial open source (TerminusDB). We use the web ontology language (OWL) as a schema language, but made two important - practical - modifications: 1) we dispense with the open world interpretation; and 2) insist on the unique name assumption. This provides us with a rich modelling language which delivers constraints on the shapes in the graph. Additiona…

I was "stuck" working with a bunch of leading academics and researchers on a SemWeb project using OWL/RDF, in collaboration with DARPA and the US Department of Defense, around 2008-2009. You are absolutely correct that they are hostile to anything outside of their "ideology". The awful, horrific performance of the RDF/OWL databases compared to the impure, heretical evil Neo4j that they despised for its practicality..…

Are you referring to the BFO crowd? I would be interested in your thoughts about BFO itself if thats the case.
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