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Kick-Off for the BMWi project SAKE

February 3, 2015 - 11:39 am by Ricardo Usbeck - No comments »

Hi all!

One of AKSW’s Big Data Project, SAKE – Semantische Analyse Komplexer Ereignisse (SAKE – Semantic Analysis of Complex Events) kicked-off in Karlsruhe. SAKE is one of the winners of the Smart Data Challenge and is funded by the German BMWi (Bundesministerium für Wirtschaft und Energie) and has a duration of 3 years. Within this project, AKSW will develop powerful methods for analysis of industrial-scale Big Linked Data in real time. To this end, the team will extend existing frameworks like LIMES, QUETSAL and FOX. Together with USU AG, Heidelberger Druckmaschinen, Fraunhofer  IAIS and AviComp Controls novel methods for tackling Business Intelligence challenges will be devised.

More info to come soon!

Stay tuned!

Axel on behalf of the SAKE team

AKSW Colloquium: Ricardo Usbeck and Ivan Ermilov on Monday, February 2, 3.00 p.m.

February 2, 2015 - 12:00 pm by Ricardo Usbeck - No comments »

GERBIL – General Entity Annotation Benchmark Framework by Ricardo Usbeck

Abstract

The need to bridge between the unstructured data on the document Web and the structured data on the Data Web has led to the development of a considerable number of annotation tools. Those tools are hard to compare since published results are calculated on diverse datasets and measured in different units.

We present GERBIL, a general entity annotation system based on the BAT-Framework. GERBIL offers an easy-to-use web-based platform for the agile comparison of annotators using multiple datasets and uniform measuring approaches. To add a tool to GERBIL, all the end user has to do is to provide a URL to a REST interface to its tool which abides by a given specification. The integration and benchmarking of the tool against user-specified datasets is then carried out automatically by the GERBIL platform. Currently, out platform provides results for 9 annotators and 11 datasets with more coming. Internally, GERBIL is based on the Natural Language Programming Interchange Format (NIF) and provide Java classes for implementing APIs for datasets and annotators to NIF. For the paper see here.

Towards Efficient and Effective Semantic Table Interpretation by Ziqi Zhang presented by Ivan Ermilov

Abstract

Ivan will present a paper that describes TableMiner by Ziqi Zhang, the first semantic Table Interpretation method that adopts an incremental, mutually recursive and bootstrapping learning approach seeded by automatically selected ‘partial’ data from a table. TableMiner labels columns containing named entity mentions with semantic concepts that best describe data in columns, and disambiguates entity content cells in these columns. TableMiner is able to use various types of contextual information outside tables for Table Interpretation, including semantic markups (e.g., RDFa/microdata annotations) that to the best of our knowledge, have never been used in Natural Language Processing tasks. Evaluation on two datasets shows that compared to two baselines, TableMiner consistently obtains the best performance. In the classification task, it achieves significant improvements of between 0.08 and 0.38 F1 depending on different baseline methods; in the disambiguation task, it outperforms both baselines by between 0.19 and 0.37 in Precision on one dataset, and between 0.02 and 0.03 F1 on the other dataset. Observation also shows that the bootstrapping learning approach adopted by TableMiner can potentially deliver computational savings of between 24 and 60% against classic methods that ‘exhaustively’ processes the entire table content to build features for interpretation.

About the AKSW Colloquium

This event is part of a series of events about Semantic Web technology. Please see http://wiki.aksw.org/Colloquium for further information about previous and future events. As always, Bachelor and Master students are able to get points for attendance and there is complimentary coffee and cake after the session.

Two AKSW Papers at #WWW2015 in Florence, Italy

January 20, 2015 - 4:09 pm by Ricardo Usbeck - No comments »

Hello Community!
We are very pleased to announce that two of our papers were accepted for presentation at WWW 2015.  The papers cover novel approaches for Key Discovery while Linking Ontologies and a benchmark framework for entity annotation systems. In more detail, we will present the following papers:
Visit us from the 18th to the 22nd May in Florence, Italy and enjoy the talks. More information on these publications at http://aksw.org/Publications.
Cheers,
Ricardo on behalf of AKSW

Highlights of the 1st Meetup on Question Answering Systems – Leipzig, November 21st

November 24, 2014 - 10:09 am by AliKhalili - No comments »

On November 21st, AKSW group was hosting the 1st meetup on “Question Answering” (QA) systems. In this meeting, researchers from AKSW/University of Leipzig, CITEC/University of Bielefeld, Fraunhofer IAIS/University of BonDERI/National University of Ireland and the University of Passau presented the recent results of their work on QA systems. The following themes were discussed during the meeting:

  • Ontology-driven QA on the Semantic Web. Christina Unger presented Pythia system for ontology-based QA. Slides are available here.
  • Distributed Semantic Models for achieving scalability & consistency on QA. André Freitas presented TREO and EasyESA which employ vector-based approach for semantic approximation.
  • Template-based QA. Jens Lehmann presented TBSL for Template-based Question Answering over RDF Data.
  • Keyword-based QA. Saeedeh Shekarpour presented SINA approach for semantic interpretation of user queries for QA on interlinked data.
  • Hybrid QA over Linked Data. Ricardo Usbeck presented HAWK for hybrid question answering using Linked Data and full-text indizes.
  • Semantic Parsing with Combinatory Categorial Grammars (CCG). Sherzod Hakimov. Slides are available here.
  • QA on statistical Linked Data. Konrad Höffner presented LinkedSpending and RDF Data Cube vocabulary to apply QA on statistical Linked Data.
  • WDAqua (Web Data and Question Answering) project. Christoph Lange presented the WDAqua project which is part of the EU’s Marie Skłodowska-Curie Action Innovative Training Networks. WDAqua focuses on answering different aspects of the question, “how can we answer complex questions with web data?”
  • OKBQA (Open Knowledge Base & Question-Answering). Axel-C. Ngonga Ngomo presented OKBQA which aims to bring cutting edge experts in knowledge base construction and application in order to create an extensive architecture for QA systems which has no restriction on programming languages.
  • Open QA. Edgard Marx presented open source question answering framework that unifies QA approaches from several domain experts.

The meetup decided to meet biannually to fuse efforts. All agreed upon investigating existing architecture for question answering systems to be able to offer a promising, collaborative architecture for future endeavours. Join us next time! For more information contact Ricardo Usbeck.

Ali and Ricardo on behalf of the QA meetup

Announcing GERBIL: General Entity Annotator Benchmark Framework

November 20, 2014 - 10:08 am by Ricardo Usbeck - No comments »

Dear all,

We are happy to announce GERBIL – a General Entity Annotation Benchmark Framework, a demo can be found at! With GERBIL, we aim to establish a highly available, easy quotable and liable focal point for Named Entity Recognition and Named Entity Disambiguation (Entity Linking) evaluations:

  • GERBIL provides persistent URLs for experimental settings. By these means, GERBIL also addresses the problem of archiving experimental results.
  • The results of GERBIL are published in a human-readable as well as a machine-readable format. By these means, we also tackle the problem of reproducibility.
  • GERBIL provides 11 different datasets and 9 different entity annotators. Please talk to us if you want to add yours.

To ensure that the GERBIL framework is useful to both end users and tool developers, its architecture and interface were designed with the following principles in mind:

  • Easy integration of annotators: We provide a web-based interface that allows annotators to be evaluated via their NIF-based REST interface. We provide a small NIF library for an easy implementation of the interface.
  • Easy integration of datasets: We also provide means to gather datasets for evaluation directly from data services such as DataHub.
  • Extensibility: GERBIL is provided as an open-source platform that can be extended by members of the community both to new tasks and different purposes.
  • Diagnostics: The interface of the tool was designed to provide developers with means to easily detect aspects in which their tool(s) need(s) to be improved.
  • Portability of results: We generate human- and machine-readable results to ensure maximum usefulness and portability of the results generated by our framework.

We are looking for your feedback!

Best regards,

Ricardo Usbeck for The GERBIL Team