Tag: Paper

Instrumenting Continuous Knowledge Extraction, Sharing, and Benchmarking

by Marco Brambilla, posted in big data, data science, event

This is a contribution in response to the Call for Linked Research for the workshop at ESWC 2017 entitled Enabling Decentralised Scholarly Communication.

Authors: Marco Brambilla, Emanuele Della Valle, Andrea Mauri, Riccardo Tommasini.

Affiliation: Politecnico di Milano, DEIB, Data Science Lab. Milano, Italy.

You can also read and download the full article in PDF
“Nanos gigantum humeris insidentes”
(Bernard of Chartres, 1115 ca.)

Introduction

Science aims at  creating new knowledge upon the existing one, from the observation of physical phenomena, their modeling and empirical validation. This combines the well known motto “standing on the shoulders of giants” (attributed to Bernard of Chartres and subsequently rephrased by Isaac Newton) with the need of trying and validating new experiments.
However, knowledge in the world continuously evolves, at a pace that cannot be traced even by large crowdsourced bodies of knowledge such as Wikipedia. A large share of generated data are not currently analysed and consolidated into exploitable information and knowledge (Ackoff 1989). In particular, the process of ontological knowledge discovery tends to focus on the most popular items, those which are mostly quoted or referenced, and is less effective in discovering less popular items, belonging to the so-called long tail , i.e. the portion of the entity’s distribution having fewer occurrences (Brambilla 2016).
This becomes a challenge for practitioners, enterprises and scholars / researchers, which need to be up to date to innovation and emerging facts. The scientific community also need to make sure there is a structured and formal way to represent, store and access such knowledge, for instance as ontologies or linked data sources.
Our idea is to propose a vision towards a set of (possibly integrated) publicly available tools that can help scholars keeping the pace with the evolving knowledge. This implies the capability of integrating informal sources, such as social networks, blogs, and user-generated content in general. One can conjecture that somewhere, within the massive content shared by people online, any low-frequency, emerging concept or fact has left some traces. The challenge is to detect such traces, assess their relevance and trustworthiness, and transform them into formalized knowledge (Stieglitz 2014).An appropriate set of tools that can improve effectiveness of knowledge extraction, storage, analysis, publishing and experimental benchmarking could be extremely beneficial for the entire research community across fields and interests.

Our Vision towards Continuous Knowledge Extraction and Publishing

We foresee a paradigm where knowledge seeds can be planted, and subsequently grow, finally leading to the generation and collection of new knowledge, as depicted in the exemplary process shown below: knowledge seeding (through types, context variables, and example instances), growing (for instance by exploring social media), and harvesting for extracting concepts (instances and types).

ske-paradigm
We advocate for a set of tools that, when implemented and integrated, enable  the following perspective reality:

  • possibility of selecting any kind of source of raw data, independently of their format, type or  semantics (spanning quantitative data, textual content, multimedia content), covering both data streams or pull-based data sources;
  • possibility of applying different data cleaning and data analysis pipelines to the different sources, in order to increase data quality and abstraction / aggregation;
  • possibility of integrating the selected sources;
  • possibility of running homogeneous knowledge extraction processes of the integrated sources;
  • possibility of publishing the results of the analysis and semantic enrichment as new and further (richer) data sources and streams, in a coherent, standard and semantic way.

This enables generation of new sources which in turn can be used in subsequent knowledge extraction processes of the same kind. The results of this process must be available at any stage to be shared for building an open, integrated and continuously evolving knowledge for research, innovation, and dissemination purposes.

A Preliminary Feasibility Perspective

Whilst beneficial and powerful, the vision we propose is far from being achieved nowadays.  However, we are convinced that the vision is not out of reach in the mid term. To give a hint of this, we report here our experience with the research, design and implementation of a few tools that point in the proposed direction:

  1. Social Knowledge Extractor (SKE) is a publicly available tool for discovering emerging knowledge by extracting it from social content. Once instrumented by experts through very simple initialization, the tool is capable of finding emerging entities by means of a mixed syntactic-semantic method. The method uses seeds, i.e. prototypes of emerging entities provided by experts, for generating candidates; then, it associates candidates to feature vectors, built by using terms occurring in their social content, and then ranks the candidates by using their distance from the centroid of seeds, returning the top candidates as result. The tool can run continuously or with periodic iterations, using the results as new seeds. Our research on this has been published in (Brambilla et al., 2017), a simplified implementation is currently available online for demo purposes
    at http://datascience.deib.polimi.it/social-knowledge/,
    and the code is available as open-source under an Apache 2.0 license on GitHub at https://github.com/DataSciencePolimi/social-knowledge-extractor.
  2. TripleWave is a tool for disseminating and exchanging RDF streams on the Web. At the purpose of  processing information streams in real-time and at Web scale, TripleWave integrates nicely with RDF Stream Processing (RSP) and Stream Reasoning (SR) as solutions to combine semantic technologies with stream and event processing techniques. In particular, it integrates with an existing ecosystem of solutions to query, reason and perform real-time processing over heterogeneous and distributed data streams. TripleWave can be fed with existing Web streams (e.g. Twitter and Wikipedia streams) or time-annotated RDF datasets (e.g. the Linked Sensor Data dataset) and it can be invoked through both pull- and push-based mechanisms, thus enabling RSP engines to automatically register and receive data from TripleWave. The tool has been described in (Mauri et al., 2016) and the code is available as open-source on GitHub at https://github.com/streamreasoning/TripleWave/.
  3. RSPlab enables efficient design and execution of reproducible experiments,  as well as sharing of the results. It integrates two existing RSP benchmarks (LSBench and CityBench) and two RSP engines (C-SPARQL engine and CQELS). It provides a programmatic environment to: deploy in the cloud RDF Streams and RSP engines; interact with them using TripleWave and RSP Services; continuously monitor their performances and collect statistics. RSPlab is released as open-source under an Apache 2.0 license, is currently under submission at ISWC – Resources Track and is available on GitHub
    at https://github.com/streamreasoning/rsplab.

Conclusions

We believe that knowledge intaking by scholars is going to become more and more time consuming and expensive, due to the amount of knowledge that is being built and shared everyday. We envision a comprehensive approach based on integrated tools that allow data collection, cleaning, integration, analysis and semantic representation that can be run continuously  for keeping the formalized knowledge bases aligned with the evolution of knowledge, with limited cost and high recall on the facts and concepts that emerge or decay. These tools do not need to be implemented by the same vendor or provider; we instead advocate for opensource publishing of all the implementations, as well as for the definition of an agreed-upon integration platform that allows them all to colloquiate appropriately.

Outlook on Research Resource Sharing

As we envisioned an ecosystem that includes, but is not limited to, modules for extraction, sharing and benchmarking, two research questions require investigation in the immediate future:
First, how can we design and publish new resources for such an ecosystem? Do they exist already? It is important to understand what else is available out there.  Researchers commonly support their scientific studies with resources that can benefit the whole community, if released. The release process must comply with a scientific method that ensures repeatability and reproducibility. However, a standard agreed-upon methodology that guide this process does not exists yet.
Second, how should we combine these resources towards shared research workflows? To investigate this research question, we need a platform that enables researchers to deploy their resources and interact with the ecosystem. Therefore, we call for an open discussion about how this integration should be done.

References

  • Russell L. Ackoff. From data to wisdom. Journal of applied systems analysis 16, 3–9 (1989).

  • Marco Brambilla, Stefano Ceri, Florian Daniel, Emanuele Della Valle. On the quest for changing knowledge. In Proceedings of the Workshop on Data-Driven Innovation on the Web – DDI 16. ACM Press, 2016. Link

  • Stefan Stieglitz, Linh Dang-Xuan, Axel Bruns, Christoph Neuberger. Social Media Analytics. Business & Information Systems Engineering 6, 89–96 Springer Nature, 2014. Link

  • Marco Brambilla, Stefano Ceri, Emanuele Della Valle, Riccardo Volonterio, Felix Xavier Acero Salazar. Extracting Emerging Knowledge from Social Media. In Proceedings of the 26th International Conference on World Wide Web – WWW 17. ACM Press, 2017. Link

  • Andrea Mauri, Jean-Paul Calbimonte, Daniele Dell’Aglio, Marco Balduini, Marco Brambilla, Emanuele Della Valle, Karl Aberer. TripleWave: Spreading RDF Streams on the Web. 140–149 In Lecture Notes in Computer Science. Springer International Publishing, 2016. Link

(*) Note: the current version includes content in response to an online open review.

Modeling and Analyzing Engagement in Social Network Challenges

by Marco Brambilla, posted in social network, social network analysis

Within a completely new line of research, we are exploring the power of modeling for human behaviour analysis, especially within social networks and/or in occasion of large scale live events. Participation to challenges within social networks is a very effective instrument for promoting a brand or event and therefore it is regarded as an excellent marketing tool.
Our first reasearch has been published in November 2016 at WISE Conference, covering the analysis of user engagement within social network challenges.
In this paper, we take the challenge organizer’s perspective, and we study how to raise the
engagement of players in challenges where the players are stimulated to
create and evaluate content, thereby indirectly raising the awareness about the brand or event itself. Slides are available on slideshare:

We illustrate a comprehensive model of the actions and strategies that can be exploited for progressively boosting the social engagement during the challenge evolution. The model studies the organizer-driven management of interactions among players, and evaluates
the effectiveness of each action in light of several other factors (time, repetition, third party actions, interplay between different social networks, and so on).
We evaluate the model through a set of experiment upon a real case, the YourExpo2015 challenge. Overall, our experiments lasted 9 weeks and engaged around 800,000  users on two different social platforms; our quantitative analysis assesses the validity of the model.

The paper is published by Springer here.

cross-platform_pdf

 

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Community-based Crowdsourcing – Our paper at WWW2014 SOCM

by Marco Brambilla, posted in social network

Today Andrea Mauri presented our paper “Community-based Crowdsourcing” at the SOCM Workshop co-located with the WWW 2014 conference.

SOCM is the 2nd International Workshop on the Theory and Practice of Social Machines and is an interesting venue for discussing instrumentation, tooling, and software system aspects of online social network. The full program of the event is here.

Our paper is focused on community-based crowdsourcing applications, i.e. the ability of spawning crowdsourcing tasks upon multiple communities of performers, thus leveraging the peculiar characteristics and capabilities of the community members.
We show that dynamic adaptation of crowdsourcing campaigns to community behaviour is particularly relevant. We demonstrate that this approach can be very e ffective for obtaining answers from communities, with very di fferent size, precision, delay and cost, by exploiting the social networking relations and the features of the crowdsourcing task. We show the approach at work within the CrowdSearcher platform, which allows con figuring and dynamically adapting crowdsourcing campaigns tailored to different communities. We report on an experiment demonstrating the eff ectiveness of the approach.

The figure below shows a declarative reactive rule that dynamically adapts the crowdsourcing campaign by moving the task executions from a community of workers to another, when the average quality score of the community is below some threshold.

The slides of the presentation are available on Slideshare. If you want to know more or see some demos, please visit:

http://crowdsearcher.search-computing.org

 

The full paper will be available on the ACM Digital Library shortly.

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A bottom-up, knowledge-aware approach to integrating and querying web data services – ACM Trans. on the Web

by Marco Brambilla, posted in data science

The October 2013 issue of the ACM Transaction on the Web includes an article of ours on bottom-up domain model design of connected web data sources. This is becoming a more and more important problem as a wealth of data services is becoming available on the Web. Indeed, building and querying Web applications that effectively integrate Web content is increasingly important. However, schema integration and ontology matching with the aim of registering data services often requires a knowledge-intensive, tedious, and error-prone manual process. In the paper we tackle this issue as described below.

The paper has been authored by Stefano Ceri, Silvia Quarteroni and myself within the research project Search Computing.

The full paper is available for download on the ACM Digital Library (free of charge, courtesy of the ACM Author-izer service) through this URL:

http://dl.acm.org/citation.cfm?id=2493536

This is the summary of the contribution:

We present a bottom-up, semi-automatic service registration process that refers to an external knowledge base and uses simple text processing techniques in order to minimize and possibly avoid the contribution of domain experts in the annotation of data services. The first by-product of this process is a representation of the domain of data services as an entity-relationship diagram, whose entities are named after concepts of the external knowledge base matching service terminology rather than being manually created to accommodate an application-specific ontology. Second, a three-layer annotation of service semantics (service interfaces, access patterns, service marts) describing how services “play” with such domain elements is also automatically constructed at registration time. When evaluated against heterogeneous existing data services and with a synthetic service dataset constructed using Google Fusion Tables, the approach yields good results in terms of data representation accuracy.

We subsequently demonstrate that natural language processing methods can be used to decompose and match simple queries to the data services represented in three layers according to the preceding methodology with satisfactory results. We show how semantic annotations are used at query time to convert the user’s request into an executable logical query. Globally, our findings show that the proposed registration method is effective in creating a uniform semantic representation of data services, suitable for building Web applications and answering search queries.

The bibtex reference is as follows:

@article{QBC2013,
 author = {Quarteroni, Silvia and Brambilla, Marco and Ceri, Stefano},
 title = {A bottom-up, knowledge-aware approach to integrating and querying web data services},
 journal = {ACM Trans. Web},
 issue_date = {October 2013},
 volume = {7},
 number = {4},
 month = nov,
 year = {2013},
 issn = {1559-1131},
 pages = {19:1--19:33},
 articleno = {19},
 numpages = {33},
 url = {http://doi.acm.org/10.1145/2493536},
 doi = {10.1145/2493536},
 acmid = {2493536},
 publisher = {ACM},
 address = {New York, NY, USA},
 keywords = {Web data integration, Web data services, Web services, natural language Web query, service querying, structured Web search},
} 


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ICWE 2008 contributions
				

			 by Marco Brambilla, posted in data science		
			

	

		
I’ve published some of my current work on Web engineering at the ICWE 2008 conference. This year the conference will be held in July 2008 in Yorktown Heights (USA), at the IBM T.J. Watson research center.  The paper that will be presented there are:


    

  • M. Brambilla, C. Tziviskou. “Modeling Ontology-Driven Personalization of Web Contents”
    • 

  • M. Brambilla, J.C. Preciado, M. Linaje, and F. Sanchez-Figueroa, “Business Process -based Conceptual Design of Rich Internet Applications”
    • 

  • M. Brambilla, A. Origgi. “MVC-Webflow: an AJAX Tool for Online Modeling of MVC-2 Web Applications”, Demo
    • 



Proceedings will be available in electronic form by IEEE Press.