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Writing a Survey – Steps, Advantages, Limitations and Examples

February 13, 2015 - 10:10 am by AmrapaliZaveri - No comments »

What is a Survey?

A survey or systematic literature review is a text of a scholarly paper, which includes the current knowledge including substantive findings, as well as theoretical and methodological contributions to a particular topic. Literature reviews use secondary sources, and do not report new or original experimental work [1].

A systematic review is a literature review focused on a research question, trying to identify, appraise, select and synthesize all high quality research evidence and arguments relevant to that question. Moreover, a literature review is comprehensive, exhaustive and repeatable, that is, the readers can replicate or verify the review.

Steps to perform a survey

  • Select two independent reviewers

  • Look for related/existing surveys

    • If it exists, see how long back it was done. If it was 10 years ago, you can go ahead and update it.

  • Formulate research questions

  • Devise eligibility criteria

  • Define search strategy – keywords, journals, conferences, workshops to search in

  • Retrieve further potential article using search strategy and also directly contacting top researchers in the field

  • Compare chosen articles among reviewers and decide a core set of papers to be included in the survey

  • Perform Qualitatively and Quantitatively on the selected set of papers

  • Report on the results

Advantages of writing a survey

There are several benefits/advantages of conducting a survey, such as:

  • A survey is the best way to get an idea of the state-of-the-art technologies, algorithms, tools etc. in a particular field

  • One can get a clear birds-eye overview of the current state of that field

  • It can serve as a great starting point for a student or any researcher thinking of venturing into that particular field/area of research

  • One can easily acquire updated information of a subject by referring to a review

  • It gives researchers the opportunity to formalize different concepts of a particular field

  • It allows one to identify challenges and gaps that are unanswered and crucial for that subject

Limitations of a survey

However, there are a few limitations that must be considered before undertaking a survey such as:

  • Surveys can tend to be biased, thus it is necessary to have two researchers, who perform the systematic search for the articles independently

  • It is quite challenging to unify concepts, especially when there are different ideas referring to the same concepts developed over several years

  • Indeed, conducting a survey and getting the article published is a long process

Surveys conducted by members of the AKSW group

In our group, three students conducted comprehensive literature reviews on three different topics:

  • Linked Data Quality: The survey covers 30 core papers, which focus on providing quality assessment methodologies for Linked Data specifically. A total of 18 data quality dimensions along with their definitions and 69 metrics are provided. Additionally, the survey contributes a comparison of 12 tools, which perform quality assessment of Linked Data [2].

  • Ubiquitous Semantic Applications: The survey presents a thorough analysis of 48 primary studies out of 172 initially retrieved papers.  The results consist of a comprehensive set of quality attributes for Ubiquitous Semantic Applications together with corresponding application features suggested for their realization. The quality attributes include aspects such as mobility, usability, heterogeneity, collaboration, customizability and evolvability. The proposed quality attributes facilitate the evaluation of existing approaches and the development of novel, more effective and intuitive Ubiquitous Semantic Applications [3].

  • User interfaces for semantic authoring of textual content: The survey covers a thorough analysis of 31 primary studies out of 175 initially retrieved papers. The results consist of a comprehensive set of quality attributes for SCA systems together with corresponding user interface features suggested for their realization. The quality attributes include aspects such as usability, automation, generalizability, collaboration, customizability and evolvability. The proposed quality attributes and UI features facilitate the evaluation of existing approaches and the development of novel more effective and intuitive semantic authoring interfaces [4].

Also, here is a presentation on “Systematic Literature Reviews”: http://slidewiki.org/deck/57_systematic-literature-review.

References

[1] Lisa A. Baglione (2012) Writing a Research Paper in Political Science. Thousand Oaks: CQ Press.

[2] Amrapali Zaveri, Anisa Rula, Andrea Maurino, Ricardo Pietrobon, Jens Lehmann and Sören Auer (2015), ‘Quality Assessment for Linked Data: A Survey’, Semantic Web Journal. http://www.semantic-web-journal.net/content/quality-assessment-linked-data-survey

[3] Timofey Ermilov, Ali Khalili, and Sören Auer (2014). ;Ubiquitous Semantic Applications: A Systematic Literature Review’. Int. J. Semant. Web Inf. Syst. 10, 1 (January 2014), 66-99. DOI=10.4018/ijswis.2014010103 http://dx.doi.org/10.4018/ijswis.2014010103

[4] Ali Khalili and Sören Auer (2013). ‘User interfaces for semantic authoring of textual content: A systematic literature review’, Web Semantics: Science, Services and Agents on the World Wide Web, Volume 22, October 2013, Pages 1-18 http://www.sciencedirect.com/science/article/pii/S1570826813000498

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, DL-Learner, 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