Tag Archives: SPARQL

GSoC 2020 recap

With 45 project proposals, this GSoC edition marked a new record for DBpedia.

GSoc and DBpedia Sticker

Oh, what a year! For the 9th year in a row, we were part of this incredible journey of young ambitious developers who joined us as an open source organization to work on a GSoC coding project all summer. 

Each year has brought us new project ideas, many amazing students and mostly great project results that shaped the future of DBpedia. 

Even though Covid-19 changed a lot in the world, it couldn’t shake GSoC much. The program, designed to mentor youngsters from afar is almost too perfect for the current world situation. One of the advantages of Google Summer of Code is, especially in times like these, the chance to work on projects remotely, but still obtain a first deep dive into Open Source projects like us – DBpedia. 

Meet the students and their projects

This year, we had notably more applications than in the previous ones. With 45 project proposals, this GSoC edition marked a new record for DBpedia. Throughout the summer program, our seven finalists worked intensely on their challenging DBpedia projects with great outcomes to show to the public. Projects ranged from extending our DBpedia extraction framework to a DBpedia Database project as well as to an online tool to generate RDF from DBpedia abstracts. If you want to have deeper insights into our GSoC student’s work you can find their blogs and repos in the following list. Check them out! 

Thanks to all our mentors around the world for joining us in this endeavour, for mentoring with kindness and technical expertise. A huge shout out to those who have been by our side for so many years in a row. Many thanks to Tommaso Soru, Beyza Yaman, Diego Moussalem, Edgard Marx, Mariano Rico, Thiago Castro Ferreira, Luca Virgili as well as Sebastian Hellmann, Stuart Chan, Amandeep Srivastava, Julio Hernandez and Jan Forberg. 

Mentor Summit

During the previous years you might have noticed that we always organized a little lottery to decide which mentor or organization admin can join the annual GSoC mentor summit. As this year’s event will be held online, space is not limited to 300 something mentors but is open to all organization admins and mentors alike. The GSoC Virtual Mentor Summit takes place October 15- 16, 2020 and this year we hope all our mentors will find the time to join and exchange with fellow mentors from around dozens of open source projects. 

After GSoC is before the next GSoC

We can not wait for the 2021 edition. Likewise, if you are an ambitious student who is interested in open source development and working with DBpedia you are more than welcome to either contribute your own project idea or apply for project ideas we offer starting in early 2021.

In case you like to mentor a project do not hesitate to also get in touch with us via dbpedia@infai.org

Stay tuned, frequently check Twitter, LinkedIn or the DBpedia Forum to stay in touch and don’t miss your chance of becoming a crucial force in this endeavour as well as a vital member of the DBpedia community.

See you soon,

yours

DBpedia Association

New Prototype: Databus Collection Feature

We are thrilled to announce that our Databus Collection Feature for the DBpedia Databus has been developed and is now available as a prototype. It simplifies the way to bundle your data and use it in your application.

A new Databus Collection Feature? How come, and how does it work? Read below and find out how using the DBpedia Databus becomes easier by the day and with each new tool.

Motivation

With more and more data being uploaded to the databus we started to develop test applications using that data. The SPARQL endpoint offers a central hub to access all metadata for datasets uploaded to the databus provided you know how to write SPARQL queries. The metadata includes the download links of the data files – it was, therefore, possible to pass a SPARQL query to an application, download the actual data and then use for whatever purpose the app had.

The Databus Collection Editor

The DBpedia Databus now provides an editor for collections. A collection is basically a labelled SPARQL query that is retrievable via URI. Hence, with the collection editor you can group Databus groups and artifacts into a bundle and publish your selection using your Databus account. It is now a breeze to select the data you need, share the exact selection with others and/or use it in existing or self-made applications.

If you are not familiar with SPARQL and data queries, you can think of the feature as a shopping cart for data: You create a new cart, put data in it and tell your friends or applications where to find it. Quite neat, right?

In the following section, we will cover the user interface of the collection editor.

The Editor UI

Firstly, you can find the collection editor by going to the DBpedia Databus and following the Collections link at the top or you can get there directly by clicking here.

What you will see is the following:

General Collection Info

Secondly, since you do not have any collections yet, the editor has already created an empty collection named “Unnamed” for you. At the right side next to the label and description you will find a pen icon. By clicking the icon or the label itself you can edit its content. The collection is not published yet, so the Collection URI is blank.

Whenever you are not logged in or the collection has not been published yet, the editor will also notify you that your changes are only saved in your local browser cache and NOT remotely on our server. Keep that in mind when clearing your cache. Publishing the collection however is easy: Simply log into (or create) your Databus account and hit the publish button in the action bar. This will open up a modal where you can pick your unique collection id and hit publish again. That’s it!

The Collection Info section will now show the collection URI. Following the link will take you to the HTML representation of your collection that will be visible to others. Hitting the Edit button in the action bar will bring you back to the editor.

Collection Hierarchy

Let’s have a look at the core piece of the collection editor: the hierarchy view. A collection can be a bundle of different Databus groups and artifacts but is not limited to that. If you know how to write a SPARQL query, you can easily extend your collection with more powerful selections. Therefore, the hierarchy is split into two nodes:

  • Generated Queries: Contains all queries that are generated from your selection in the UI
  • Custom Queries: Contains all custom written SPARQL queries

Both, hierarchy nodes have a “+” icon. Clicking on this button will let you add generated or custom queries respectively.

Custom Queries

If you hit the “+” icon on the Custom Queries node, a new node called “Custom Query” will appear in the hierarchy. You can remove a custom query by clicking on the trashcan icon in the hierarchy. If you click the node it will take you to a SPARQL input field where you can edit the query.

To make your collection more understandable for others, you can even document the query by adding a label and description.

Writing Your Own Custom Queries

A collection query is a SPARQL query of the form:

SELECT DISTINCT ?file WHERE {
    {
        [SUBQUERY]
    }
    UNION
    {
        [SUBQUERY]
    }
    UNION
    ...
    UNION
    {
        [SUBQUERY]
    }
}

All selections made by generated and custom queries will be joined into a single result set with a single column called “file“. Thus it is important that your custom query binds data to a variable called “file” as well.

Generated Queries

Clicking the “+” icon on the Generated Queries node will take you to a search field. Make use of the indexed search on the Databus to find and add the groups and artifacts you need. If you want to refine your search, don’t worry: you can do that in the next step!

Once the artifact or group has been added to your collection, the Add to Collection button will turn green. Once you are done you can go back to the Editor with Back to Hierarchy button.

Your hierarchy will now contain several new nodes.

Group Facets, Artifact Facets and Overrides

Group and artifacts that have been added to the collection will show up as nodes in the hierarchy. Clicking a node will open a filter where you can refine your dataset selection. Setting a filter to a group node will apply it to all artifact nodes unless you override that setting in any artifact node manually. The filter set in the group node is shown in the artifact facets in dark grey. Any overrides in the artifact facets will be highlighted in green:

Group Nodes

A group node will provide a list of filters that will be applied to all artifacts of that group:

Artifact Nodes

Artifact nodes will then actually select data files which will be visible in the faceted view. The facets are generated dynamically from the available variants declared in the metadata.

Example: Here we selected the latest version of the databus dump as n-triple. This collection is already in use: The collection URI is passed to the new generic lookup application, which then creates the search function for the databus website. If you are interested in how to configure the lookup application, you can go here: https://github.com/dbpedia/lookup-application. Additionally, there will also be another blog post about the lookup within the next few weeks

Use Cases

The DBpedia Databus Collections are useful in many ways.

  • You can share a specific dataset with your community or colleagues.
  • You can re-use dataset others created
  • You can plug collections into databus-ready applications and avoid spending time on the download and setup process
  • You can point to a specific piece of data (e.g. for testing) with a single URI in your publications
  • You can help others to create data queries more easily

We hope you enjoy the Databus Collection Feature and we would love to hear your feedback! You can leave your thoughts and suggestions in the new DBpedia Forum. Feedback of any kinds is highly appreciated since we want to improve the prototype as fast and user-driven as possible! Cheers!

A big thanks goes to DBpedia developer Jan Forberg who finalized the Databus Collection Feature and compiled this text.

Yours

DBpedia Association

Better late than never – GSOC 2019 recap & outlook GSoC 2020

  • Pinky: Gee, Brain, what are we gonna do this year?
  • Brain: The same thing we do every year, Pinky. Taking over GSoC.

And, this is exactly what we did. We had been accepted as one of 206 open source organizations to participate in Google Summer of Code (GSoC) again. More than 25 students followed our call for project ideas. In the end, we chose six amazing students and their project proposals to work with during summer 2019. 
In the following post, we will show you some insights into the project ideas and how they turned out. Additionally, we will shed some light onto our amazing team of mentors who devoted a lot of time and expertise in mentoring our students. 

Meet the students and their projects

A Neural QA Model for DBpedia by Anand Panchbhai

With booming amount of information being continuously added to the internet, organising the facts and serving this information to the users becomes a very difficult task. Currently, DBpedia hosts billions of data points and corresponding relations in the RDF format. Accessing data on DBpedia via a SPARQL query is difficult for amateur users, who do not know how to write a query. This project tried to make this humongous linked data available to a larger user base in their natural languages (now restricted to English). The primary objective of the project was to translate natural language questions to a valid SPARQL query. Click here if you want to check his final code.

Multilingual Neural RDF Verbalizer for DBpedia by Dwaraknath Gnaneshwar

Presently, the generation of Natural Language from RDF data has gained substantial attention and has also been proven to support the creation of Natural Language Generation benchmarks. However, most models are aimed at generating coherent sentences in English, while other languages have enjoyed comparatively less attention from researchers. RDF data is usually in the form of triples, <subject, predicate, object>. Subject denotes the resource, the predicate denotes traits or aspects of the resource and expresses the relationship between subject and object. In this project, we aimed to create a multilingual Neural Verbalizer, ie, generating high-quality natural-language text from sets of RDF triples in multiple languages using one stand-alone, end-to-end trainable model. You can follow up on the progress and outcome of the project here. 

Predicate Detection using Word Embeddings for Question Answering over Linked Data by Yajing Bian

Knowledge-based question-answering system (KBQA) has demonstrated an ability to generate answers to natural language from information stored in a large-scale knowledge base. Generally, it completes the analysis challenge via three steps: identifying named entities, detecting predicates and generate SPARQL queries. In these three steps, predicate detection identifies the KB relation(s) a question refers to. To build a predicate detection structure, we identified all possible named entity first, then collected all predicates corresponding to the above entities. What follows is to calculate the similarity between problem and candidate predicates using a multi-granularity neural network model (MGNN). To find the globally optimal entity-predicate assignment, we use a joint model which is based on the result of entity linking and predicate detection process rather than considering the local predictions (i.e. most possible entity or predicate) as the final result. More details on the project are available here

A tool to generate RDF triples from DBpedia abstract by  Jayakrishna Sahit

The main aim of this project was to research and develop a tool in order to generate highly trustable RDF triples from DBpedia abstracts. In order to develop such a tool, we implemented algorithms which would take the output generated from the syntactic analyzer along with DBpedia spotlight’s named entity identifiers. Further information and the project’s results can be found here

A transformer of Attention Mechanism for Long-context QA by Stuart Chan

In this GSoC project, I choose to employ the language model of the transformer with an attention mechanism to automatically discover query templates for the neural question-answering knowledge-based model. The ultimate goal was to train the attention-based NSpM model on DBpedia with its evaluation against the QALD benchmark. Check here for more details on the project.

Workflow for linking External datasets by Jaydeep Chakraborty

The requirement of the project was to create a workflow for entity linking between DBpedia and external data sets. We aimed at an approach for ontology alignment through the use of an unsupervised mixed neural network. We explored reading and parsing the ontology and extracted all necessary information about concepts and instances. Additionally, we generated semantic vectors for each entity with different meta information like entity hierarchy, object property, data property, and restrictions and designed a User Interface based system which showed all necessary information about the workflow. Further info, download details and project results are available here

Meet our Mentors

First of all, a big shout out and thank you to all mentors and co-mentors who helped our students to succeed in their endeavours.

  • Aman Mehta, former GSoC student and current junior mentor, recently interned as a software engineer at Facebook, London.
  • Beyza Yaman, a senior mentor and organizational admin, Post-Doctoral Researcher based in ADAPT, Dublin City University, former Springer Nature-DBpedia intern and former research associate at the InfAI/University of Leipzig. She is responsible for the Turkish DBpedia and her field of interests are information retrieval, data extraction and integration over Linked Data.
  • Tommaso Soru, senior mentor and organizational admin. I’m a Machine Learning & AI enthusiast, Data Scientist at Data Lens Ltd in London and a PhD candidate at the University of Leipzig. 

“DBpedia is my window to the world of semantic data, not only for its intuitive interface but also because its knowledge is organised in a simple and uncomplicated way”

Tommaso Soru, GSoC 2019
  • Amandeep Srivastava, Junior Mentor and analyst at Goldman Sachs. He’s a huge fan of Christopher Nolan and likes to read fiction books in his free time.
  • Diego Moussalem, Senior mentor, Senior Researcher at Paderborn University, an active and vital member of the Portuguese DBpedia Chapter
  • Luca Virgili, currently a Computer Science PhD student at the Polytechnic University of Marche.He was a GSoC student for a year and a GSoC mentor for 2 years in DBpedia. 
  • Bharat Suri, former GSOC student, Junior Mentor, Masters degree in Computer Science at The Ohio State University

“I have thoroughly enjoyed both my years of GSoC with DBpedia and I plan to stay and help out in whichever way I can”

Bharat Suri, GSoC 2019
  • Mariano Rico, senior mentor,  Senior Doctor Researcher at Ontology Engineering Group, Universidad Politécnica de Madrid.
  • Nausheen Fatma, senior mentor, Data Scientist, Natural Language Processing, Machine Learning at Info Edge (naukri.com).
  • Ram G Athreya long-term GSoC mentor, Research Engineer at Viv Labs, Bay Area, San Francisco. 
  • Ricardo Usbeck, team leader ‘Conversational AI and Knowledge Graphs’ at Fraunhofer IAIS.
  • Rricha Jalota, former GSoC students, current senior mentor, developer in the Data Science Group at University of Paderborn, Germany 

“The reason why I love collaborating with DBpedia (apart from the fact that, it’s a powerhouse of knowledge-driven applications) is not only it gave me my first big break to the amazing field of NLP but also to the world of open-source!”

Rricha Jalota, GSoC 2019

In addition, we also like to thank the rest of our mentor team namely, Thiago Castro Ferreira, Aashay Singhal and Krishanu Konar, former GSoC student and current senior mentor, for their great work.  

Mentor Summit Recap 

This GSoC marked the 15th consecutive year of the program and was the 8th season in a row for DBpedia. As usual in each year we had two of our mentors, Rricha Jalota and Aashay Singhal joining the annual GSoC mentor summit. Selected mentors get the chance to meet each other and engage in a vital knowledge and expertise exchange around various GSoC related and non-related topics. Apart from more entertaining activities such as games, a scavenger hunt and a guided trip through Munich mentors also discussed pressing questions such as “why is it important to fail your students” or “how can we have our GSoC students stay and contribute for long”.

After GSoC is before the next GSoC

If you are interested in either mentoring a DBpedia GSoC project or if you want to contribute to a project of your own we are happy to have you on board. There are a few things to get you started.

Likewise, if you are an ambitious student who is interested in open source development and working with DBpedia you are more than welcome to either contribute your own project idea or apply for project ideas we offer starting in early 2020.

Stay tuned, frequently check Twitter or the DBpedia Forum to stay in touch and don’t miss your chance of becoming a crucial force in this endeavour as well as a vital member of the DBpedia community.

See you soon,

yours

DBpedia Association

Retrospective: GSoC 2018

With all the beta-testing, the evaluations of the community survey part I and part II and the preparations for the Semantics 2018 we lost almost sight of telling you about the final results of GSoC 2018. Following we present you a short recap of this year’s students and projects that made it to the finishing line of GSoC 2018.

 

Et Voilà

We started out with six students that committed to GSoC projects. However, in the course of the summer, some dropped out or did not pass the midterm evaluation. In the end, we had three finalists that made it through the program.

Meet Bharat Suri

… who worked on “Complex Embeddings for OOV Entities”. The aim of this project was to enhance the DBpedia Knowledge Base by enabling the model to learn from the corpus and generate embeddings for different entities, such as classes, instances and properties.  His code is available in his GitHub repository. Tommaso Soru, Thiago Galery and Peng Xu supported Bharat throughout the summer as his DBpedia mentors.

Meet Victor Fernandez

.. who worked on a “Web application to detect incorrect mappings across DBpedia’s in different languages”. The aim of his project was to create a web application and API to aid in automatically detecting inaccurate DBpedia mappings. The mappings for each language are often not aligned, causing inconsistencies in the quality of the RDF generated. The final code of this project is available in Victor’s repository on GitHub. He was mentored by Mariano Rico and Nandana Mihindukulasooriya.

Meet Aman Mehta

.. whose project aimed at building a model which allows users to query DBpedia directly using natural language without the need to have any previous experience in SPARQL. His task was to train a Sequence-2-Sequence Neural Network model to translate any Natural Language Query (NLQ) into the corresponding sentence encoding SPARQL query. See the results of this project in Aman’s GitHub repositoryTommaso Soru and Ricardo Usbeck were his DBpedia mentors during the summer.

Finally, these projects will contribute to an overall development of DBpedia. We are very satisfied with the contributions and results our students produced.  Furthermore, we like to genuinely thank all students and mentors for their effort. We hope to be in touch and see a few faces again next year.

A special thanks goes out to all mentors and students whose projects did not make it through.

GSoC Mentor Summit

Now it is the mentors’ turn to take part in this year GSoC mentor summit, October 12th till 14th. This year, Mariano Rico and Thiago Galery will represent DBpedia at the event. Their task is to engage in a vital discussion about this years program, about lessons learned, highlights and drawbacks they experienced during the summer. Hopefully, they return with new ideas from the exchange with mentors from other open source projects. In turn, we hope to improve our part of the program for students and mentors.

Sit tight, follow us on Twitter and we will update you about the event soon.

Yours DBpedia Association

DBpedia at LSWT 2018

Unfortunately, with the new GDPR, we experienced some trouble with our Blog. That is why this post is published a little later than anticipated.

There you go.

With our new strategic orientation and the emergence of the DBpedia Databus, we wanted to meet some DBpedia enthusiasts of the German DBpedia Community.

The recently hosted 6th LSWT (Leipzig Semantic Web Day) on June 18th, was the perfect platform for DBpedia to meet with researchers, industry and other organizations to discuss current and future developments of the semantic web.

Under the motto “Linked Enterprises Data Services”, experts in academia and industry talked about the interlinking of open and commercial data of various domains such as e-commerce, e-government, and digital humanities.

Sören Auer, DBpedia endorser and board member as well as director of TIB, the German National Library of Science and Technology, opened the event with an exciting keynote. Recapping the evolution of the semantic and giving a glimpse into the future of integrating more cognitive processes into the study of data,  he highlighted the importance of AI, deep learning, and machine learning. They are as well as cognitive data, no longer in their early stages but advanced to fully grown up sciences.

Shortly after, Sebastian Hellmann, director of the DBpedia Association, presented the new face of DBpedia as a global open knowledge network. DBpedia is not just the most successful open knowledge graph so far, but also has a deep inside knowledge about all connected open knowledge graphs (OKG) and how they are governed. 

With our new credo connecting data is about linking people and organizations, the global DBpedia platform aims at sharing efforts of OKG governance, collaboration, and curation to maximize societal value and develop a linked data economy.

 

The DBpedia Databus functions as Metadata Subscription Repository, a platform that allows exchanging, curate and access data between multiple stakeholders. In order to maximize the potential of your data, data owners need a WebID to sign their Metadata with a private key in order to make use of the full Databus services.  Instead of one huge monolithic release every 12 months the Databus enables easier contributions and hence partial releases (core, mapping, wikidata, text, reference extraction) at their own speed but in much shorter intervals (monthly). Uploading data on the databus means connecting and comparing your data to the network. We will offer storage services, free & freemium services as well as data-as-a-service.  A first demo is available via http://downloads.dbpedia.org/databus

During the lunch break, LSWT participants had time to check out the poster presentations. 4 of the 18 posters used DBpedia as a source. One of them was Birdory, a memory game developed during the Coding Da Vinci hackathon, that started in April 2018. Moreover, other posters also used the DBpedia vocabulary.

Afternoon Session

In the afternoon, participants of LSWT2018 joined hands-on tutorials on SPARQL and WebID. During the SPARQL tutorial, ten participants learned about the different query types, graph patterns, filters, and functions as well as how to construct SPARQL queries step by step with the help of a funny Monty Python example.

Afterwards, DBpedia hosted a hands-on workshop on WebID, the password-free authentication method using semantics. The workshop aimed at enabling participants to set up a public/private key, a certificate, and a WebID.  Everything they needed to bring was a laptop and an own webspace. Supervised by DBpedia’s executive director Dr. Sebastian Hellmann and developer Jan Forberg, people had to log-into a test web service at the end of the session, to see if everything worked out. All participants seemed well satisfied with the workshop –  even if not everyone could finish it successfully they got a lot of individual help and many hints. For support purposes, DBpedia will stay close in touch with those participants.

 

Thanks to Institut für Angewandte Informatik as well to the LEDS -project and eccenca for organizing LSWT2018 and keeping the local semantic web community thriving.

 

Upcoming Events:

We are currently looking forward to our next DBpedia meetup in Lyon, France on July 3rd and the DBpedia Day co-located with Semantics 2018 in Vienna. Contributions to both events are still welcome. Send your inquiry to dbpedia@infai.org.

 

Yours

 

DBpedia Association