International Semantic Web Conference (ISWC) 2018 Trip Report

ISWC has been my go-to conference every year. This time it was very special for two reasons. First of all, it was my 10 year anniversary of attending ISWC (first one was ISWC2008 in Karlsruhe where I presented a poster that ultimately became the basis of my PhD research and also the foundational software of Capsenta). Too bad my dear friend and partner in crime, Olaf Hartig, missed out (but for good reasons!). I only missed ISWC2010 in Shanghai; other than that, I’ve attended each one and I plan to continue attending them (New Zealand next year!)

The other reason why this was a special ISWC is because we officially launched Gra.fo, a visual, collaborative, real-time ontology and knowledge graph schema editor, which we have been working on for over 2 years in stealth mode.


THE Workshop: This year at ISWC, I co-organized THE Workshop on Open Problems and Emerging New Topics in Semantic Web Technology. The goal was to organize a true workshop where attendees would actually discuss and get work done.

Let’s say that we may have been a bit ambitious but at the end it turned out very well. In the first part of the morning, everybody was encouraged to stand up and on the spot talk for a minute about their problem. We gathered 19 topics. The rest of the morning, we self organized into clusters and each group continued to discuss and finalized with a wrap-up.

The goal was to submit the problems to THE Workshop website. Looks like the attendees have not done their homework (you know who you are!). We had great feedback about this format and we will consider submitting it again for next year and improve the format.


VOILA: I’ve been attending the Visualization and Interaction for Ontologies and Linked Data (VOILA) Workshop for the past couple of years (guess why 🙂 ) and luckily I was able to catch the last part of it. My take away is that there is a lot of cool things going on in this area but the research problems that are being addressed are not always clear. Furthermore, prototypes are engineered and evaluated but it’s not clear who is this tool for. Who is your user? I brought this up in my trip report from last year. This community MUST partner with other researchers in HCI and Social Science in order to harden the scientific rigor. Additionally, there are cool ideas that would be interesting to see if there is commercial viability.


SHACL:  I attended the Validating RDF data tutorial by Jose Emilio Labra Gayo. I came in trying to find an answer to the following question: Is SHACL ready for industry prime time? The answer is complicated but unfortunately I have to say, not yet. First of all, even though SHACL is the W3C recommendation, there is another proposal called ShEx from Jose Emilio’s group. He acknowledges his bias but if you look at the ShEx and SHACL side by side, you can argue for one or the other objectively. For example, ShEx supports recursive constraints, but SHACL doesn’t (There was a research paper on this topic, Semantics and Validation of Recursive SHACL, … but it’s research!). Nevertheless, the current SHACL specification is stable and technically ready to be used in prime time. The problem is the lack of commercial tools for enterprise data. Jose Emilio is keeping a list of SHACL/ShEx implementations but all except for TopQuadrant, are (academic) prototypes. Seems like Stardog is planning to officially support it in their 6.0 release. At this stage, I was expecting to see a standalone SHACL validator that can take as input RDF data or a SPARQL endpoint and run the validations. With all due respect, but these kind of situations are embarrassing for this community and industry: apparently a standard is needed, a recommendation is made, but at the end there is no industry implementation and uptake (one or two is not enough). We live in a “build it and they will come” world and this does not make us look good. </rant>. On a positive note, I think we are very close to the following: create a SHACL to SPARQL translator that starts out by supporting a simple profile of SHACL (cardinality constraints). This way anybody can use this on any RDF graph database. Somebody should build this, and we should support it as a community, not just academics but also having industry users behind it.

Hat tip to Jose Emilio for the nice SHACL/ShEx Playground and to EricIovka and Dimitris for making their book, Validating RDF, available for free (html version).


SOLID: I missed out on the Decentralizing the Semantic Web workshop. I heard it was packed and I guess it did help that Tim Berners-Lee was there presenting on Solid. Later on, I had the chance to talk to TimBL about Solid and his new startup Inrupt. The way I understood Solid and what Inrupt is doing is through the following analogy: They have designed a brand new phone and the app store infrastructure around it (i.e. Solid). However, people already have phones (web apps that store your data) so they need to convince others to use their phone. Who would they convince and how? Ideally, they want to convince everybody on earth… literally, but they can start out with people who are concerned about data ownership privacy. My skepticism is that the majority of the people in the world don’t care about it. Jennifer Golbeck’s keynote touched on this topic and stated that young people don’t care about privacy but the older you get, the more you start caring. Solid is definitely solving a problem but I question the size of the market (i.e. who cares about this problem). Good luck Inrupt team!

Enterprise Knowledge Graphs: One of the highlights of ISWC was the Enterprise Knowledge Graph panel. This was actually a great panel (commonly I find that panels are very boring). The participants were from Microsoft, Facebook, Ebay, Google and IBM. I had two main takeaways.
1) For all of these large companies, the biggest challenge is identify resolution. Decades of Record Linkage/Entity Resolution/etc research and we are still far away from solving this problem… at scale. Context is the main issue.
2) The most important takeaway from the entire conference was: NONE OF THESE COMPANIES USE RDF/OWL/SPARQL… AND IT DOESN’T MATTER! I was actually very happy to hear them say this in front of the entire semantic web academic community. At the end, the ideas of linking data, using triples, having tight/loose schemas, reasoning, all at scale have come out of the semantic web research community and started to permeate into the industry. It’s fine if they are not using the exact W3C Semantic Web Standards. The important thing is that the ideas are being passed on to the real world. It’s time to listen to the real world and see what problems they have and bring it back for research. This is part of the scientific method!
Notes from each panelist:

Another possible answer to Yolanda Gil’s question is the recently launched dataCommons.org.
The final question to the panel: what are the challenges that the scientific community should be working on. Their answers:


Not everybody is a Google: The challenges stated by the Enterprise Knowledge Graph panelist are for the Googles of the world. Not everybody is a Google. For a while now, I feel that a large research focus is on tackling problems for the Googles of the world. But what about the other spectrum? My company Capsenta is building knowledge graphs for very large companies and I can tell you that building a beautiful, clean knowledge graph from even a single structured data source, let alone a dozen, is not easy. I believe that the semantic web, and even the database community have forgotten about this problem and dismissed this as day to day engineering challenges. The talk “Integrating Semantic Web in the Real World: A Journey between Two Cities” that I have been giving this year details all the open engineering, scientific and social challenges we are encountering. One of those problems is defining mappings from source to target schemas. Even though the Ontology Matching workshop and the Ontology Alignment Evaluation Initiative have been going on for over a decade… the research results and systems do not address the real world problems that we see at Capsenta in our day to day. We need to research the real world social-technical phenomenons of data integration. One example is dealing with complex mappings. I was very excited to see the work of Wright State University and their best resource paper nominated work “A Complex Alignment Benchmark: GeoLink Dataset”. This is off to a good start but there is still a lot of work to be done. Definitely a couple of PhDs can come out of this.


Natasha Noy’s keynote:  I really enjoyed her keynote, which I summarized: 

She also provided some insight on Google Dataset search:


Vanessa Evers’ keynote was incredible refreshing, because it successfully brought to the attention of the semantic web community the problems encounter to create social intelligent robots. Guess what’s missing? Semantics and reasoning!


Industry:  I was happily surprised to see a lot of industry folks this year. The session I chaired had about 100 people.

Throughout the week I saw and met with startups like Diffbot and Kobai; folks from Finance: FINRA, Moodys, Federal Reserve, Intuit, Bloomberg, Thomson Reuters/Refinitiv, Credit Suisse; Graph Databases companies: Amazon Neptune, Allegrograph, Marklogic, Ontotext’s GraphDB, Stardog; Healthcare: Montefiore Health Systems, Babylon Health, Numedii; the big companies: Google, Microsoft, IBM, Facebook, Ebay; and many others such as Pinterest, Springer, Elsevier, Expert Systems, Electronic Arts. Great to see so much industry attending ISWC! All the Industry papers are available online.

Best Papers: The best papers highlighted the theme of the conference: Knowledge Graphs and Real World relevance. The best paper went to an approach to provide explanations of facts in a Knowledge Graph.

The best student research paper was a theoretical paper on canonicalisation of monotone SPARQL queries, which has a clear real world usage: improve caching for SPARQL endpoints.

The best resource paper address the problem of creating a gold standard data set for data linking, a crucial task to create Knowledge Graphs at scale. They present an open source software framework to build Games with a Purpose in order to help create a gold standard of data by motivating users through fun incentives.

The best in use paper went to the paper that describes the usage of semantic technology underpinning Wikidata, the Wikipedia Knowledge Graph.

Finally, the best poster went to VoCaLS: Describing Streams on the Web and the Best demo award went to WebVOWL Editor.


DL: Seems like DL this year meant Deep Learning and not Description Logic. I don’t think there was any paper on Description Logic, a big switch from past years.


Students and Mentoring:  I enjoyed hanging out with PhD students and offering advice at the career panel during the Doctoral Consortium and at the mentoring lunch.

During the lunch on Wednesday we talked about science being a social process and it was very nice that this also came up on Thursday during Natasha’s keynote


Striving for Gender Equality: I am extremely proud of the semantic web research community because they are an example of always striving for gender equality. This year they had a powerful statement: conference was organized entirely by women (plus Denny and Rafael) and  they had 3 amazing women keynotes. Additionally, the local organizers did a tremendous job!

Furthermore, Ada Lovelace Day, which is held every year on the second Tuesday of October, occurred during ISWC. So what did the organizers do? They held the Ada Lovelace celebration where we had a fantastic panel discussing efforts on striving for gender equality in the sciences (check out sciencestories.io!)

The event ended with Wikipedia Edit-a-thon where we created and edited Wikipedia pages of female scientist. In particular, we created Wikipedia pages for female scientist in our community: Natasha Noy, Yolanda Gil, Lora Aroyo. It was a true honor to have the opportunity to create the english wikipedia page of Asunción Gómez Pérez, who has been incredibly influential in my life.

More trip reportsCheck out Helena Deus’ and Paul Groth’s ISWC Trip reports (which I haven’t read so it wouldn’t bias mine)

What an awesome research community: I am very lucky to consider the Semantic Web community my research home. It’s a work hard, play hard community.

We were at a very beautiful venue:

We like to sing

We like to have great dinners and dance:

We even throw jam sessions and parties:

And just like last year, I recorded the Jam session:

ISWC Jam Session

Posted by Juan Sequeda on Thursday, October 11, 2018

Posted by Juan Sequeda on Thursday, October 11, 2018

Posted by Juan Sequeda on Thursday, October 11, 2018

See you next year in New Zealand

… and then in 2020 … Athens, Greece!

Gra.fo, a visual, collaborative, real-time ontology and knowledge graph schema editor

A common frustration we’ve encountered is the lack of adequate tooling around ontology and knowledge graph schema design. Many tools exist– some are overly complex, some are very expensive, and none allow one to work visually, collaboratively and in real time on a document with multiple concurrent users.

That is why two years ago we took half a dozen Capsenta engineers and set off to design and develop a solution. Our design principles were:

Real World: Focus on solving problems that we encounter in the real world with our customers and users.
Understand our audience: We work with data geeks but also business and domain experts– our solution has to satisfy them both.
Minimal: Let’s not boil the ocean; be focused and practical.
Do not reinvent the wheel: A lot of great research and scientific results exist that should be leveraged.

With that in mind, we are very pleased to announce the official launch of Gra.fo, a visual, collaborative, and real-time ontology and knowledge graph schema editor. It is the only editor where you can:

– Visually design your schema by dragging and dropping Concepts, Attributes, Relationships and Specializations– what we lovingly refer to as C/A/R/S.
– Share your document with other users and grant view-only, commenting, or editing permissions.
– Collaborate in real-time with multiple users.
– Comment on individual C/A/R/S with other users.
– Search for C/A/R/S.
– Track document history, name a version and restore to any previous version.

E-commerce Knowledge Graph Schema in Gra.fo

Like other knowledge graph editing software, Gra.fo lets you Import and Export existing RDF/OWL ontologies. Property Graphs are also supported. For an overview of Gra.fo’s features, check out this short demo:

After two years of stealth mode, we officially launched Gra.fo last week at the 17th International Semantic Web Conference (ISWC2018) in Monterey. The reception was universally positive. It was also very cool to demo Gra.fo to Sir Tim Berners-Lee!

Demoing Gra.fo to Sir Tim Berners Lee
Discussions with Sir Tim Berners-Lee on Gra.fo and Solid.

Gra.fo is currently the only visual, collaborative, and real-time ontology and knowledge graph schema editor in existence. But that’s not good enough for us. We want to be the best knowledge graph editor, period! Toward that end we are actively working on several new features with more to come:

– Git: Commit and push your document to Git.
– Import Mapping: View R2RML mappings within Gra.fo.
– API: Access and build knowledge graphs programmatically.

Please check it out at https://gra.fo/. We offer one month gratis at the Team level so feel free to try out all that Gra.fo offers. Serving the community is important to us so please let us know what you need!

This is just the beginning!