Department of Informatics – DDIS

Dynamic and Distributed Information Systems Group

Double success at WWW for Tobias Grubenmann

14. March 2018 | Suzanne Tolmeijer | Comments Off on Double success at WWW for Tobias Grubenmann

Good news for PhD student Tobias Grubenmann: not one, but two of his papers got accepted at the next Web Conference in April. This conference, formerly known as the WWW Conference, is a highly regarded conference in the field of the world wide web. Tobias will be there to present ‘Financing the Web of Data with Delayed-Answer Auctions‘, in which he and his colleagues suggest an auction mechanism with delayed answers to a query on the Web of Data, to make sure sponsored data gets privileged over non-sponsored data. With this new concept, a first step is taken towards a free yet financial sustainable Web of Data.

Besides this paper, he will also present his work at the PhD Symposium, where PhD students can present their ongoing research. In his paper, called ‘Monetization Strategies for the Web of Data‘, he introduces his take on how to make the Web of Data sustainable by finding ways to finance the creation and maintenance of content on the Web of Data.


Abgelegt unter: ConferenceDDIS-People

‘Everyone should learn how to deal with data’

7. March 2018 | Suzanne Tolmeijer | Comments Off on ‘Everyone should learn how to deal with data’

For their first news bulletin of 2018, Swiss ICT association Asut interviewed Prof. Bernstein concerning the theme ‘Kids and Codes: education for a digital world’. In this interview, Prof. Bernstein expressed the opinion that in our current information society, it is important for people to learn the skills necessary to deal with digitalisation, such as coding, and more importantly, how to deal with data. To read the entire article, click here (article in German).

Which skills are needed in the 21st century? How should digitisation change our education? Source: Asut



Abgelegt unter: Press

Digital Democracy – Too risky or the chance of a generation?

25. January 2018 | Suzanne Tolmeijer | Comments Off on Digital Democracy – Too risky or the chance of a generation?

In an article on SWI on the risks and chances of a digital democracy, Prof. Dr. Abraham Bernstein gives his view on the matter. He argues in favour of “making citizens aware of political issues online and via smartphones, fostering discussions, getting quick feedback from the people on political issues, and simplifying the collection of signatures”. More about the current state of the debate can be found here.

Democracy and political engagement right in your pocket?


Abgelegt unter: AllgemeinPress

Abraham Bernstein on SRF Radio about digitalisation and politics

14. December 2017 | Suzanne Tolmeijer | Comments Off on Abraham Bernstein on SRF Radio about digitalisation and politics

Increasing digitalisation is happening in many different domains in Switzerland, but politics does not seem to be among them (yet). In radio show ‘Heute Morgen’ on SRF1, different experts were asked about how digitalisation could impact politics in Switzerland. Abraham Bernstein thinks politicians should be more courageous and adapt partially obsolete political processes by using the available technology. More people can be involved in the debates around political issues using tech, an opinion he also expresses with other researchers in their manifesto on digital democracy. The radio fragment can be found here (German audio and text).

What if voting was only one click away? Image Source

Abgelegt unter: Press

Shen Gao successfully defends his thesis

11. December 2017 | Suzanne Tolmeijer | Comments Off on Shen Gao successfully defends his thesis

On the 4th of December, Shen Gao successfully defended his thesis on ‘Efficient Processing and Reasoning of Semantic Streams’. Both his supervisors Prof. Dr. Abraham Bernstein of the University of Zürich and Prof. Dr. Jeff Pan of the University of Aberdeen were present to challenge Shen with questions and ultimately grant him his doctor’s title. As for the future, he has been hired to join Google. We wish him all the best!

Shen presenting his thesis

Dr. Gao!

Abgelegt unter: DDIS-People

NZZ Z-Magazine contribution by Abraham Bernstein

29. November 2017 | Suzanne Tolmeijer | Comments Off on NZZ Z-Magazine contribution by Abraham Bernstein

Prof. Dr. Bernstein was approached by NZZ to give his opinion on the following statement: ‘Algorithmen treffen bessere Entscheidungen’. (Algorithms make better decisions)

As both Professor in Informatics and Director of the Digital Society Initiative, he felt the following way:

“Menschen entscheiden anders als Algorithmen, ihre Stärken und Schwächen unterscheiden sich deshalb. Computer sind schnell und urteilen bei denselben Voraussetzungen immer gleich. Wir Menschen haben verschiedene Ansichten und kommen oft zu unterschiedlichen Schlüssen. Wir lassen uns durch unseren Gemütszustand beeinflussen und müssen motiviert werden. Bei raschen, wohldefinierten Entscheidungen, die ohne Beeinflussung zu fällen sind, haben Computer oft die Oberhand. Wenn es aber um komplexe, vage definierte Fragen geht, dann kommen Menschen – vor allem in Gruppen – meistens zu besseren, originelleren Lösungen. Das Ziel ist deshalb, die Stärken von menschlicher und künstlicher Intelligenz zu kombinieren, um die Gesellschaft weiterzubringen”

For those that do not speak German, Abraham highlights the differences between how humans and computers function, and states that the goal should be to use the strengths of both humans and computers to advance society.

Abgelegt unter: Allgemein

Abraham Bernstein shares knowledge on first Swiss Digital Day

29. November 2017 | Suzanne Tolmeijer | Comments Off on Abraham Bernstein shares knowledge on first Swiss Digital Day

digitalswitzerland, with help of many partners, organised the first Swiss Digital Day last November 21st. Many talks, games, and other activities were organised throughout the country to discuss how digitalisation will impact Switzerland. Of course, UZH’s own Digital Society Initiative (DSI) would not miss such a great initiative, and helped fuel the discussions at Zürich HB.

Abraham Bernstein, director of the DSI, was present to participate. Among other activities, he discussed the impact of AI and whether there would still be professions in 2050. The pictures below, as well as a more general overview of the DSI activities during that day, can be found here.

Abraham Bernstein during panel discussion

Federal Councillor Johann Schneider-Ammann talking with Abraham Bernstein

Abgelegt unter: Allgemein

Success for DDIS at ISWC 2017

10. November 2017 | Suzanne Tolmeijer | Comments Off on Success for DDIS at ISWC 2017

This year’s ISWC conference in Vienna proved successful for DDIS: two main track papers, two workshop papers, a tutorial, a workshop, and a keynote speech at the doctoral consortium by Prof. Abraham Bernstein. Join us in a report about the highlights.

This year’s edition of the 16th International Semantic Web Conference, an important conference in the field, was visited by three of DDIS’s group members: Tobias Grubenmann, Dr. Daniele Dell’Aglio and Prof. Dr. Abraham Bernstein.

One of the main track papers, ‘Challenges of source selection in the WoD’ (1), presented by Tobias, was selected as a spotlight paper. It argues for a renewed effort to find novel join-cardinality approximation techniques for source selection or a change of paradigm in query execution to settings, after showing the limitations of Bloom Filters.

Tobias presenting

Tobias presenting ‘Challenges of source selection in the WoD’

The second research, ‘Computing Authoring Tests from Competency Questions: Experimental Validation’ (2), was co-authored by Daniele. The paper experimentally investigates a technique, Competency Question Ontology Authoring, to see if it does what it promises: assess if an ontology is actually capturing users’ expectations.

Daniele and Tobias also presented two papers at the DeSemWeb workshop. Daniele presented a paper titled ‘On a Web of Data Streams’ (3). Streams are getting more and more popular, but there is no agreement on which protocols and rules we should follow for exchanging and processing them on the web. This article summarizes the requirements we need to address to realize a Web of data streams, and proposes a novel protocol, WeSP, and shows its feasibility.

The other paper, titled ‘Decentralizing the Semantic Web: Who will pay to realize it?’ (4), was presented by Tobias. The vision of a marketplace for decentralized data following basic Web of Data principles and its challenges were discussed.

A workshop on Web Stream Processing, co-hosted by Daniele, targeted the community interested in stream processing in the semantic web context. The event attracted more than 30 attendees, with six talks discussing ongoing studies on stream processing, from querying streams in the web to theoretical results on stream reasoning. (5)

Daniele also co-ran a tutorial called How to Build a Stream Reasoning Application on techniques used to perform reasoning over data streams. After starting with the foundations on extensions of RDF and SPARQL to manage streams, methods to perform DL and ASP were discussed and tried out by the participants. (6)

Finally, Abraham Bernstein and Natasha Noy of Google gave a keynote at the Doctoral Consortium. The keynote named “Is this really Science: Evaluating research contributions” gave an overview to the scientific method and its evaluation in the Semantic Web domain. The keynote was well received – it was even tweeted about by senior researchers from the semantic web community.

Abraham and Natasha presenting

Abraham and Natasha presenting (picture by Lora Aroyo via Twitter)

Natasha and Abraham wrote up the key points of the presentation in their report called “Is This Really Science? The Semantic Webber’s Guide to Evaluating Research Contributions”. (7)

It was a fruitful conference at a great venue, and we look forward to the next edition!

Welcome reception

The Welcome reception at the Vienna City Hall








Abgelegt unter: ConferenceSemantic Web

Patrick de Boer defends his thesis

9. October 2017 | Suzanne Tolmeijer | Comments Off on Patrick de Boer defends his thesis

On September 13th Patrick de Boer successfully defended his thesis “Crowd Process Design: How to coordinate crowds to solve complex topics”. In his thesis Patrick researched how to programmatically coordinate large crowds towards solving a given problem efficiently. He is planning to use his gathered knowledge in a start-up: PeakData GmbH. We wish him all the best.

Congratulations Patrick!

Patrick with his graduation hat




Abgelegt unter: AllgemeinDDIS-People

Impression of Wikidata Zürich Workshop at IFI

9. October 2017 | Suzanne Tolmeijer | Comments Off on Impression of Wikidata Zürich Workshop at IFI

On September 14, the Wikidata Zurich Workshop took place at IFI. The event organised by UZH, Open Data Zurich, Wikimedia Switzerland and Open Data CH, was attended by around 30 people coming from different backgrounds such as industry, governmental organisations and universities. The main goal of the workshop was to provide information and training about Wikidata, the “free knowledge base that anyone can edit and use“.

The workshop had a fully-packed program, that started with an opening session by Cristina Sarasua (researcher at UZH, active member of Wikimedia Switzerland and main organiser of the event), followed by a keynote by Léa Lacroix, project manager of Wikidata at Wikimedia Germany. Léa Lacroix presented the current status of the knowledge base, mentioned the underlying principles the make Wikidata possible, and showed interesting tools that reuse data from Wikidata and help editors and data providers add (e.g. Wikidata games), watch (e.g. COOL-WD and ORES) and interlink (e.g. Mix’n’Match) Wikidata. As Léa Lacroix highlighted, some of the challenges that the Wikidata community is currently facing include improving data quality, enabling a better integration with other Wikimedia products, dealing with the community and content massive growth and collaborating with the people and organisations that donate and reuse data.

The morning continued with an introduction to Wikidata, a talk about reading Wikidata dumps and a talk where Cristina Sarasua and Oleg Lavrovsky (founder of Datalets and active member of Open Data CH) gave an introduction to the API that can be invoked to get information about Wikidata’s content, edits and contributors programmatically. In the next session, Beat Estermann (researcher of the Berner Hochschule and organiser of the Open Cultural Data Hackathon in Lausanne) gave an online talk about the importance of Wikidata for GLAM (Galleries, Libraries, Archives and Museums).

After the lunch break, that was nicely sponsored by Wikimedia Switzerland, Harmonia Amanda (experienced Wikidata editor with more than 2 million edits and active member of Wikimedia France) gave an introduction about querying Wikidata using SPARQL. The afternoon continued with a talk by Rama (active member of Wikimedia Switzerland and frequent Wikimedia Commons author), on the relation of Wikidata with Wikipedia and Wikimedia Commons. Afterwards, Cristina Sarasua gave a talk about the different ways in which data can be integrated with Wikidata. As she mentioned, the Open Data Zurich data ( is a great example of data that can complement Wikidata’s data, because it follows the notability criterion, it is of high quality data and it provides a more detailed information about sites in Zurich (e.g. districts of Zurich and fountains).

The last session was opened by Leon Kastler (software engineer at Avrios International AG, active member of Wikimedia Germany and co-organizer of the workshop), who gave an overview about developing bots in Wikidata. As he mentioned, bots can help humans edit large amounts of data, but should not be used for a one time batch data ingest. The last speakers were Radityo Prasojo (researcher at the University of Bozen-Bolzano), who explained how to develop tools for Wikidata with user scripts and showcased COOL-WD, and Finn A. Nielsen (associate professor at the Technical University of Denmark), who presented Scholia – a tool for browsing scholarly data within Wikidata.

Radityo Prasojo presenting

Photo by CSG

After the workshop, Cristina Sarasua and Leon Kastler gave a tech talk and participated as coders in HackZurich (

All the slides and other materials of the Wikidata Zurich workshop can be found at the event page. Given the success and interest shown by participants, the organisers plan to organise further events.

Special thanks go to all the people who helped us (Cristina Sarasua and Leon Kastler) in the organization: Marco Sieber and Michael Grueebler from Open Data Zurich, Ilario Valdelli and Ulrich Lantermann from Wikimedia Switzerland, and Muriel Staub from Open Data CH, as well as all our speakers and session leaders Léa Lacroix, Harmonia Amanda, Rama, Oleg Lavrovsky, Beat Estermann, Radityo Prasojo, Finn A. Nielsen. Hope to see you soon!

Abgelegt unter: Open DataSemantic Web