How do you explore a SPARQL Endpoint?
Assume you are given a URL for a SPARQL endpoint. You have no idea what data is being exposed. What do you do to explore that endpoint? What queries do you write? Juan Sequeda +1-575-SEQ-UEDA www.juansequeda.com
1st Summer Datathon on Linguistic Linked Open Data (SD-LLOD’15)
Apologies for cross-posting: 1st Summer Datathon on Linguistic Linked Open Data (SD-LLOD’15) === The 1st Summer Datathon on Linguistic Linked Open Data (SD-LLOD-15) will be held from June 15th to 19th 2015 at Residencia Lucas Olazábal of Universidad Politécnica de Madrid, Cercedilla, Madrid. See http://datathon.lider-project.eu The SD-LLOD datathon has the main goal of giving people from industry and academia practical knowledge in the field of Linked Data applied to Linguistics. The final aim is to allow participants to migrate their own (or other’s) linguistic data and publish them as Linked Data on the Web. This datathon is the first one organized in this topic worldwide and is supported by the LIDER FP7 Support Action (http://lider-project.eu/). There will be monetary prizes for the best projects. During the datathon, participants will: * Generate and publish their own Linguistic Linked Data from some existing data source. * Apply Linked Data principles and Semantic Web technologies (Ontologies, RDF, Linked Data) into the field of language resources. * Use the principal models used for representing Linguistic Linked Data, in particular lemon and NIF. * Perform Multilingual Word Sense Disambiguation and Entity Linking for the Web of Data. * Demonstrate potential benefits and applications of Linguistic Linked Data for specific use cases. The program of the summer datathon will contain three types of sessions: 1. Seminars to show novel aspects and discuss selected topics. 2. Practical sessions to introduce the basic foundations of each topic, methods, and technologies and where participants will perform different tasks using the methods and technologies presented. 3. Hacking sessions, where participants will follow the whole process of generating and publishing Linguistic Linked Data with some existing data set. Participants are expected to bring to the datathon some data set of linguistic data produced by their organizations in order to work on it during the hacking sessions and transformed into Linked Data. For participants who cannot provide their own linguistic data set, the organisers will provide one. Confirmed Invited Speakers == Rodolfo Maslias (Head of Unit Terminology Coordination, European Parliament) Piek Vossen (Vrije Universiteit Amsterdam) Christian Chiarcos (Goethe-University, Frankfurt) Marta Villegas (Universitat Pompeu Fabra, Barcelona) Registration Participants are expected to submit a short description (no more than 500 words) of their work and the resources they plan to work with during the datathon. The cost of the datathon is sponsored by the LIDER project, which includes accommodation and meals of participants. However there will be an administrative fee of 50€ for registering in the datathon. A limited amount of travelling grants will be available for attendants from less-developed countries who cannot cover their trip with other funds. Registration will be closed on 15th March. Organizers == Jorge Gracia (Universidad Politécnica de Madrid) John P. McCrae (Bielefeld University)
Re: How do you explore a SPARQL Endpoint?
On 2015-01-22 15:09, Juan Sequeda wrote: Assume you are given a URL for a SPARQL endpoint. You have no idea what data is being exposed. What do you do to explore that endpoint? What queries do you write? Juan Sequeda +1-575-SEQ-UEDA www.juansequeda.com I suspect that the obligatory query that everyone is dying to know is to get a distinct count of subjects. /me mumbles.. More realistically: * I would say that getting a sense of which vocabularies/ontologies are used is a good way to dive ib, and to come up with more specific/useful/interesting queries thereafter. * Look up and see which VoID information is available. Related to above point, e.g., void:vocabulary. * Check whether there is sufficient human-readable labels for the significant portion of the instances. * Check triples pertaining to provenance. * Check if there are sufficient interlinks to resources that presumably external to the domain in which the endpoint is at. Sorry, I'm not going to write out SPARQL queries here. Need to preserve brain-cells for the remainder of the day. -Sarven http://csarven.ca/#i
Re: How do you explore a SPARQL Endpoint?
Hi Juan
My strategy is as following
Q1 : Which types are used?
SELECT DISTINCT ?type
WHERE {?x rdf:type ?type}
Q2 : Which predicates are used?
SELECT DISTINCT ?p
WHERE {?x ?p ?o}
Q3 : Which predicates are used by instances of the type :foo found in Q1
I'm interested in
SELECT DISTINCT ?p
WHERE {?x ?p :foo}
2015-01-22 15:09 GMT+01:00 Juan Sequeda juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
*Bernard Vatant*
Vocabularies Data Engineering
Tel : + 33 (0)9 71 48 84 59
Skype : bernard.vatant
http://google.com/+BernardVatant
*Mondeca*
35 boulevard de Strasbourg 75010 Paris
www.mondeca.com
Follow us on Twitter : @mondecanews http://twitter.com/#%21/mondecanews
--
LeDA-SWAn 2015 Workshop - First call for papers
** apologies for cross posting ** FIRST CALL FOR PAPERS - LeDA-SWAn 2015 2015 International Workshop on Legal Domain And Semantic Web Applications (LeDA-SWAn 2015) http://cs.unibo.it/ledaswan2015 held during the 12th Extended Semantic Web Conference (ESWC 2015) June 1, 2015, Portoroz, Slovenia The two research areas of Legal Knowledge and Information Systems, and the Semantic Web are very much interconnected. The legal domain is an ideal field of study for Semantic Web researchers, as it uses and contributes to most of the topics that are relevant to the community. Given the complex interactions of legal actors, legal sources and legal processes, as well as the relevance and potential impact of decisions in the juridical and social processes of a country, it provides a challenging context and an important opportunity for groundbreaking research results. At the same time, Semantic Web formalisms and technologies provide a set of technical instruments which can be fruitfully adopted by legal experts to represent, interlink, and reason over legal knowledge and related aspects such as provenance, privacy, and trust. In particular, Semantic Web technology facilitates standards-based legal knowledge representation, which enables the possibility of legal information reuse over the Web. Ontologies, knowledge extraction and reasoning techniques have been studied by the Artificial Intelligence Law community for years, but only few and sparse connections with the Semantic Web community have resulted from these interactions. The aim of this workshop is to study the challenges that the legal domain poses to Semantic Web research, and how Semantic Web technologies and formalisms can contribute to address these open issues. This way, we pro- mote the use of legal knowledge for addressing Semantic Web research questions and, vice versa, to use Semantic Web technologies as tools for reasoning over legal knowledge. In particular, the workshop will look for original, high quality contributions that explore the following topics (but not limited to): - Modeling access policies to Semantic Web datasets - Semantic Web and online dispute resolution and mediation - Semantic sensor networks in lawsuits, crisis mapping, emergencies and stand-by forces - Semantic Web techniques and e-discovery in large legal document collections - Semantic Web technologies and opinion collection and analysis - Legal content and knowledge in the Linked Data - Knowledge acquisition and concept representation on annotations and legal texts - Legal ontology process and management - Legal reasoning and query in the Semantic Web - Scalability issues in representing law and legal texts - Analysis of provenance information to detect violations of norms/policies - Expressive vs. lightweight representations of legal content - Core and domain ontologies in the legal domain - Theories, design patterns and ontologies in legal argumentation - Time and legal content representation (texts, concepts, norms) - OWL approaches to reasoning and legal knowledge - Linking legal content to external resources - Provenance, trust and metadata for authoritative sources - SPARQL queries on large legal datasets - Legal knowledge extraction using NLP and ontologies - User-friendly applications and interface design to interact with legal semantic information - Publishing/reusing legal-related content in Linked Data - Rules and Automated Reasoning in the Semantic Web - Semantic Web technologies and Legal Scholarly Publishing - Law, Intellectual property and legal issues for data and schemas - Licenses for Linked Open Data - Information ethics and the Semantic Web Workshop Chairs: Silvio Peroni, University of Bologna (Italy) Serena Villata, Inria Sophia Antipolis (France) Important dates: - March 6, 2015: Paper submission deadline (23:59 Hawaii time) - April 3, 2015: Author notification - April 17, 2015: Camera-ready copies due - June 1, 2015 (afternoon): Workshop Submission instructions: All papers must represent original and unpublished work that is not currently under review. Papers will be evaluated according to their significance, originality, technical content, style, clarity, and relevance to the workshop. We welcome the following types of contributions: - Full research papers (up to 12 pages) - Short research papers (up to 6 pages) - Poster papers (up to 4 pages) - Demo papers (up to 4 pages) All submissions must be written in English and formatted according to LNCS instructions for authors: http://www.springer.com/computer/lncs?SGWID=0-164-6-793341-0 Papers are to be submitted through the Easychair Conference Management System: https://easychair.org/conferences/?conf=ledaswan2015 Publication opportunity: We are planning to publish the full conference proceedings as part of the CEUR Workshop Proceedings. In addition, relevant submissions will be considered for a further book publication.
Re: How do you explore a SPARQL Endpoint?
Hi
the most basic query is the usual query for concepts, something like:
SELECT DISTINCT ?concept
WHERE {
?uri a ?concept.
}
then, given a specific concept, you can infer from the data what are the
predicates/properties for it:
SELECT DISTINCT ?prp
WHERE {
[] ?prp a-concept.
}
and so on...
Apart from other more complex query (here we are of course omitting a lot
of important things), these two patterns are usually the most useful as a
starting point, for me.
2015-01-22 15:09 GMT+01:00 Juan Sequeda juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
Re: How do you explore a SPARQL Endpoint?
Give me all your types seems the most sensible thing to do. Otherwise full text search. On Thu, Jan 22, 2015 at 3:09 PM, Juan Sequeda juanfeder...@gmail.com wrote: Assume you are given a URL for a SPARQL endpoint. You have no idea what data is being exposed. What do you do to explore that endpoint? What queries do you write? Juan Sequeda +1-575-SEQ-UEDA www.juansequeda.com
Re: How do you explore a SPARQL Endpoint?
SELECT DISTINCT ?type
WHERE { ?x rdf:type ?type . }
SELECT DISTINCT ?p
WHERE { ?s ?p ?o . }
then
SELECT ?s
WHERE {
?s a http://uri_of_a_type
} LIMIT 100
and then
DESCRIBE http://uri_of_an_instance
or
SELECT ?p ?o
WHERE {
http://uri_of_an_instance ?p ?o .
}
Having some statistics on the types may help too :
SELECT ?type (COUNT(?instance) AS ?count)
WHERE {
?instance a ?type .
} GROUP BY ?type
2015-01-22 15:19 GMT+01:00 Luca Matteis lmatt...@gmail.com:
Give me all your types seems the most sensible thing to do.
Otherwise full text search.
On Thu, Jan 22, 2015 at 3:09 PM, Juan Sequeda juanfeder...@gmail.com
wrote:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data
is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
*Thomas Francart* - Sparna
Consultant Indépendant
Data, Sémantique, Contenus, Connaissances
web : http://sparna.fr, blog : http://blog.sparna.fr
Tel : +33 (0)6.71.11.25.97
Fax : +33 (0)9.58.16.17.14
Skype : francartthomas
Re: How do you explore a SPARQL Endpoint?
Hi Juan, All,
We are actually working on some solutions that can help people to
explore what is inside a “dataset” deployed in an endpoint, to have a
better and more exhaustive view about the information and structure of
the data.
The proposed SPARQL queries are excellent, however most of them are not
feasible in practice we are faced with timeouts and endpoint
limitations, especially with the one below (although it is quite
informative).
|SELECT ?type1 ?pred ?type2
WHERE {
?subj ?pred ?obj.
?subj a ?type1.
?obj a ?type2.
}
|
The question that you raised Juan is exactly one of the purpose of the
graph summary [1]. It provides information about the predicates,
classes, and how classes relate with each other.
In [2] is a SPARQL auto-completion tool which you can use to get
suggestions about predicates/classes in an endpoint by typing
|CTRL+SPACE|. You can have a look at [3] for more details on how to use it.
This tool uses the SPARQL endpoint to get theses recommendations.
However, a summary could just as well be used. So that in addition, you
would get better performance and useful information, since the summary
is smaller than the original data and contain info about the graph
structure.
We are working on an official specification draft that we would like to
submit to W3c.
Also, we are currently working on a *repository* similar to datahub for
providing summaries that would help end-user that have your problem, and
a solution for provider on how to provide these graph summaries
alongside their original datasets.
We think that “graph summaries” coupled with VoID and Service
Description information could help people to have a better and immediate
view about the data available for a better use of them, especially if we
really want to exploit the potentialities of Linked Open Data.
Just throwing this out there to get early feedbacks…
Cheers,
[1] http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6327436tag=1
[2] http://scampi.github.io/gosparqled/
[3] https://github.com/scampi/gosparqled
On 22/01/15 14:09, Juan Sequeda wrote:
Assume you are given a URL for a SPARQL endpoint. You have no idea
what data is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com http://www.juansequeda.com
--
Stephane Campinas
Re: How do you explore a SPARQL Endpoint?
Some other pointers and queries
from https://github.com/fadmaa/rdf-analytics/blob/master/queries.txt
== query 7 (graph summary query)==
/*
this computes the schema of an RDF dataset. This is based on the queries
generated by Sindice Sparqled:
https://github.com/sindice/sparqled/tree/master/sparql-summary/src/main/java/org/sindice/summary
See also
http://shr.wordpress.com/2011/05/05/a-shot-at-rdf-schema-discovery/ for
related topic and a way to visualise the results
/*
SELECT ?label (COUNT (?label) AS ?cardinality) ?source ?target
WHERE {
{
SELECT ?s (GROUP_CONCAT(concat('',str(?type),'')) AS ?source)
WHERE {
{
SELECT ?s ?type
WHERE {
{ ?s a ?type . }
} ORDER BY ?type
}
} GROUP BY ?s
}
?s ?label ?sSon .
OPTIONAL {
{
SELECT ?sSon (GROUP_CONCAT(concat('',str(?typeSon),'')) AS ?target)
WHERE {
{
SELECT ?sSon ?typeSon
WHERE {
{ ?sSon a ?typeSon . }
} ORDER BY ?typeSon
}
} GROUP BY ?sSon
}
}
} GROUP BY ?label ?source ?target
there is also the work of the Sindice group around graph-summary:
code here: https://github.com/sindice/sparqled/tree/master/sparql-summary
On 22 Jan 2015, at 16:25, Bernard Vatant bernard.vat...@mondeca.com wrote:
Interesting to note that the answers so far are converging towards looking
first for types and predicates, but bottom-up from the data, and not queries
looking for a declared model layer using RDFS or OWL, such as e.g.,
SELECT DISTINCT ?class
WHERE { {?class a owl:Class} UNION {?class a rdfs:Class}}
SELECT DISTINCT ?property ?domain ?range
WHERE { {?property rdfs:domain ?domain} UNION {?property rdfs:range ?range}}
Which means globally you don't think the SPARQL endpoint will expose a formal
model along with the data.
That said, if the model is exposed with the data, the values of rdf:type will
contain e.g., rdfs:Class and owl:Class ...
Of course in the ideal situation where you have an ontology, the following
would bring its elements.
SELECT DISTINCT ?o ?x ?type
WHERE {?x rdf:type ?type.
?x rdfs:isDefinedBy ?o.
?o a owl:Ontology }
It's worth trying, because if the dataset you query is really big, it will be
faster to look first for a declared model than asking all distinct rdf:type
2015-01-22 15:23 GMT+01:00 Alfredo Serafini ser...@gmail.com:
Hi
the most basic query is the usual query for concepts, something like:
SELECT DISTINCT ?concept
WHERE {
?uri a ?concept.
}
then, given a specific concept, you can infer from the data what are the
predicates/properties for it:
SELECT DISTINCT ?prp
WHERE {
[] ?prp a-concept.
}
and so on...
Apart from other more complex query (here we are of course omitting a lot of
important things), these two patterns are usually the most useful as a
starting point, for me.
2015-01-22 15:09 GMT+01:00 Juan Sequeda juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what data
is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
Bernard Vatant
Vocabularies Data Engineering
Tel : + 33 (0)9 71 48 84 59
Skype : bernard.vatant
http://google.com/+BernardVatant
Mondeca
35 boulevard de Strasbourg 75010 Paris
www.mondeca.com
Follow us on Twitter : @mondecanews
--
Research Assistant/Associate at the Knowledge Media Institute, Open University for the European Data Science Academy
[Apologies for cross posting] Deadline for Applications March 4th 2015. See http://kmi.open.ac.uk/jobs/#11038 for more details and an application form. We are looking for a researcher to work on a new EU funded project the European Data Science Academy (edsa-project.euhttp://edsa-project.eu) which aims to bridge the current data science skills gap through three main activities: - Demand analysis: using data mining tools scrutinizing thousands of job descriptions and technology blogs to gain a thorough understanding of the skills required in industry (which will vary by sector and region). See [1] for a small demo we created for the proposal. - Data science curricula: high-quality, multilingual and multimodal training materials (eBooks, slides, video lectures, online demonstrators and showcases, data sets, online courses) that will be usable on different platforms. See [2, 3] for previous and current projects we build upon. - Training delivery and learning analytics: To maximize outreach we will make use of some of the most popular training delivery platforms worldwide, including VideoLectures.NEThttp://VideoLectures.NET and iTunes U (since 2008 OU materials have been downloaded over 65 million times). We will use machine learning tools to develop an analytics dashboard focused on learning experiences. Any queries about the post can be directed to me. Best John 1. http://edsa-project.eu/dashboard/ 2. http://www.euclid-project.eu/ 3. http://ict-forge.eu/ _ Deputy Director, Knowledge Media Institute, The Open University Walton Hall, Milton Keynes, MK7 6AA, UK phone: 0044 1908 653800, fax: 0044 1908 653169 email: john.domin...@open.ac.ukmailto:j.b.domin...@open.ac.uk web: kmi.open.ac.uk/people/domingue/http://kmi.open.ac.uk/people/domingue/ President, STI International Amerlingstrasse 19/35, Austria - 1060 Vienna phone: 0043 1 23 64 002 - 16, fax: 0043 1 23 64 002-99 email: john.domin...@sti2.orgmailto:john.domin...@sti2.org web: www.sti2.orghttp://www.sti2.org/ -- The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England Wales and a charity registered in Scotland (SC 038302). The Open University is authorised and regulated by the Financial Conduct Authority.
Re: How do you explore a SPARQL Endpoint?
In order to explore the schema (or better said: the types of the actual
nodes and properties) you could do:
select ?type1 ?pred ?type2
where {
?subj ?pred ?obj.
?subj a ?type1.
?obj a ?type2.
}
Depending on the triple store, it could be useful to filter some trivial
types.
Il 22/01/15 15:28, Thomas Francart ha scritto:
SELECT DISTINCT ?type
WHERE { ?x rdf:type ?type . }
SELECT DISTINCT ?p
WHERE { ?s ?p ?o .. }
then
SELECT ?s
WHERE {
?s a http://uri_of_a_type
} LIMIT 100
and then
DESCRIBE http://uri_of_an_instance
or
SELECT ?p ?o
WHERE {
http://uri_of_an_instance ?p ?o .
}
Having some statistics on the types may help too :
SELECT ?type (COUNT(?instance) AS ?count)
WHERE {
?instance a ?type .
} GROUP BY ?type
2015-01-22 15:19 GMT+01:00 Luca Matteis lmatt...@gmail.com
mailto:lmatt...@gmail.com:
Give me all your types seems the most sensible thing to do.
Otherwise full text search.
On Thu, Jan 22, 2015 at 3:09 PM, Juan Sequeda
juanfeder...@gmail.com mailto:juanfeder...@gmail.com wrote:
Assume you are given a URL for a SPARQL endpoint. You have no
idea what data
is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com http://www.juansequeda.com
--
*
*
*Thomas Francart* - Sparna
Consultant Indépendant
Data, Sémantique, Contenus, Connaissances
web : http://sparna.fr, blog : http://blog.sparna.fr
Tel : +33 (0)6.71.11.25.97
Fax : +33 (0)9.58.16.17.14
Skype : francartthomas
Re: How do you explore a SPARQL Endpoint?
It's also good to start exploring with just the ?predicates, because
not all resources necessarily have a type. (Or predicates on a type
might not always be on all instances of that types).
Also, whenever you find a new type of resource - remember to explore
both what it links to
uri ?p ?o ;
and what it is linked FROM:
?s ?p uri
On 22 January 2015 at 14:46, matteo casu mattec...@gmail.com wrote:
In order to explore the schema (or better said: the types of the actual
nodes and properties) you could do:
select ?type1 ?pred ?type2
where {
?subj ?pred ?obj.
?subj a ?type1.
?obj a ?type2.
}
Depending on the triple store, it could be useful to filter some trivial
types.
Il 22/01/15 15:28, Thomas Francart ha scritto:
SELECT DISTINCT ?type
WHERE { ?x rdf:type ?type . }
SELECT DISTINCT ?p
WHERE { ?s ?p ?o .. }
then
SELECT ?s
WHERE {
?s a http://uri_of_a_type
} LIMIT 100
and then
DESCRIBE http://uri_of_an_instance
or
SELECT ?p ?o
WHERE {
http://uri_of_an_instance ?p ?o .
}
Having some statistics on the types may help too :
SELECT ?type (COUNT(?instance) AS ?count)
WHERE {
?instance a ?type .
} GROUP BY ?type
2015-01-22 15:19 GMT+01:00 Luca Matteis lmatt...@gmail.com:
Give me all your types seems the most sensible thing to do.
Otherwise full text search.
On Thu, Jan 22, 2015 at 3:09 PM, Juan Sequeda juanfeder...@gmail.com
wrote:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data
is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
Thomas Francart - Sparna
Consultant Indépendant
Data, Sémantique, Contenus, Connaissances
web : http://sparna.fr, blog : http://blog.sparna.fr
Tel : +33 (0)6.71.11.25.97
Fax : +33 (0)9.58.16.17.14
Skype : francartthomas
--
Stian Soiland-Reyes, eScience Lab
School of Computer Science
The University of Manchester
http://soiland-reyes.com/stian/work/http://orcid.org/-0001-9842-9718
Re: How do you explore a SPARQL Endpoint?
Interesting to note that the answers so far are converging towards looking
first for types and predicates, but bottom-up from the data, and not
queries looking for a declared model layer using RDFS or OWL, such as e.g.,
SELECT DISTINCT ?class
WHERE { {?class a owl:Class} UNION {?class a rdfs:Class}}
SELECT DISTINCT ?property ?domain ?range
WHERE { {?property rdfs:domain ?domain} UNION {?property rdfs:range ?range}}
Which means globally you don't think the SPARQL endpoint will expose a
formal model along with the data.
That said, if the model is exposed with the data, the values of rdf:type
will contain e.g., rdfs:Class and owl:Class ...
Of course in the ideal situation where you have an ontology, the following
would bring its elements.
SELECT DISTINCT ?o ?x ?type
WHERE {?x rdf:type ?type.
?x rdfs:isDefinedBy ?o.
?o a owl:Ontology }
It's worth trying, because if the dataset you query is really big, it will
be faster to look first for a declared model than asking all distinct
rdf:type
2015-01-22 15:23 GMT+01:00 Alfredo Serafini ser...@gmail.com:
Hi
the most basic query is the usual query for concepts, something like:
SELECT DISTINCT ?concept
WHERE {
?uri a ?concept.
}
then, given a specific concept, you can infer from the data what are the
predicates/properties for it:
SELECT DISTINCT ?prp
WHERE {
[] ?prp a-concept.
}
and so on...
Apart from other more complex query (here we are of course omitting a lot
of important things), these two patterns are usually the most useful as a
starting point, for me.
2015-01-22 15:09 GMT+01:00 Juan Sequeda juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
*Bernard Vatant*
Vocabularies Data Engineering
Tel : + 33 (0)9 71 48 84 59
Skype : bernard.vatant
http://google.com/+BernardVatant
*Mondeca*
35 boulevard de Strasbourg 75010 Paris
www.mondeca.com
Follow us on Twitter : @mondecanews http://twitter.com/#%21/mondecanews
--
Re: How do you explore a SPARQL Endpoint?
May be not just looking at the classes and properties but looking at their
frequencies using counts can give a better idea about what sort of data is
exposed. If there is a Void information it certainly helps. Tools such as
http://data.aalto.fi/visu also help. Similar approach described here [1] .
Best Regards,
Nandana
[1] - http://ceur-ws.org/Vol-782/PresuttiEtAl_COLD2011.pdf
On Thu, Jan 22, 2015 at 4:25 PM, Bernard Vatant bernard.vat...@mondeca.com
wrote:
Interesting to note that the answers so far are converging towards looking
first for types and predicates, but bottom-up from the data, and not
queries looking for a declared model layer using RDFS or OWL, such as e.g.,
SELECT DISTINCT ?class
WHERE { {?class a owl:Class} UNION {?class a rdfs:Class}}
SELECT DISTINCT ?property ?domain ?range
WHERE { {?property rdfs:domain ?domain} UNION {?property rdfs:range
?range}}
Which means globally you don't think the SPARQL endpoint will expose a
formal model along with the data.
That said, if the model is exposed with the data, the values of rdf:type
will contain e.g., rdfs:Class and owl:Class ...
Of course in the ideal situation where you have an ontology, the following
would bring its elements.
SELECT DISTINCT ?o ?x ?type
WHERE {?x rdf:type ?type.
?x rdfs:isDefinedBy ?o.
?o a owl:Ontology }
It's worth trying, because if the dataset you query is really big, it will
be faster to look first for a declared model than asking all distinct
rdf:type
2015-01-22 15:23 GMT+01:00 Alfredo Serafini ser...@gmail.com:
Hi
the most basic query is the usual query for concepts, something like:
SELECT DISTINCT ?concept
WHERE {
?uri a ?concept.
}
then, given a specific concept, you can infer from the data what are the
predicates/properties for it:
SELECT DISTINCT ?prp
WHERE {
[] ?prp a-concept.
}
and so on...
Apart from other more complex query (here we are of course omitting a lot
of important things), these two patterns are usually the most useful as a
starting point, for me.
2015-01-22 15:09 GMT+01:00 Juan Sequeda juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what
data is being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com
--
*Bernard Vatant*
Vocabularies Data Engineering
Tel : + 33 (0)9 71 48 84 59
Skype : bernard.vatant
http://google.com/+BernardVatant
*Mondeca*
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www.mondeca.com
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--
Re: linked open data and PDF
this discussion is related to the workshop we are organizing. At Sepublica http://sepublica.mywikipaper.org/drupal/ we are very much looking forward to this kind of discussions. Those of you who are planning to attend the ESWC2015 please consider submitting to Sepublica; we have a special cathegory, call for polemics. We would like to invite authors to send us a one page manuscript, 20 lines max, describing their position with respect to new technologies supporting the publication workflow: What are the most pressing issues to be addressed? What is their position with respect to the overall problem? What innovation is needed? etc. Polemics authors will have only 5 minutes to present; the format of this session is sequential, after each presentation the next follows with no questions in between. There will be a discussion and summary of all the issues at the end of all the polemics session. Deadline for polemics: April 24th 2015 On Thu, Jan 22, 2015 at 1:03 PM, Gannon Dick gannon_d...@yahoo.com wrote: Wow, there's a blast from the past*. --Gannon * past = back when URL's looked like URI's and control freaks could keep their domain holdings and ontologies on the same ledger. Not for a minute do I think this was a good thing, and in any case no fault of GRDDL. On Wed, 1/21/15, Paul Tyson phty...@sbcglobal.net wrote: Subject: Re: linked open data and PDF To: Norman Gray nor...@astro.gla.ac.uk Cc: Paul Houle ontolo...@gmail.com, Herbert Van de Sompel hvds...@gmail.com, jschnei...@pobox.com jschnei...@pobox.com, public-lod@w3.org public-lod@w3.org Date: Wednesday, January 21, 2015, 8:52 PM On Wed, 2015-01-21 at 17:16 +, Norman Gray wrote: (also it's not even really about XMP; there are all sorts of ways of scraping metadata out of objects and turning it into something which an RDF parser can read, and from that point you can start being imaginative. This is of course stupidly obvious to everyone on this list, but it's an aha! that many people haven't got yet). GRDDL, anyone? [1] I think the GRDDL spec was too narrowly scoped to XML resources. The concept is simple and ingenious, and applicable to any type of resource. Many years ago, inspired by the then-new GRDDL spec) I built a modest RDF gleaning framework for tracing software requirements through development and testing. It gleaned from requirements documents and functional specification (in MS Word format), design documents (in TeX), source code (c++), test results (in XML), and probably also plain text (csv) and MS Excel. Regards, --Paul [1] http://www.w3.org/TR/2007/REC-grddl-20070911/ -- Alexander Garcia http://www.alexandergarcia.name/ http://www.usefilm.com/photographer/75943.html http://www.linkedin.com/in/alexgarciac
Re: How do you explore a SPARQL Endpoint?
Look in the Service Description and see what they put in there. Otherwise see if there is any documentation linked from the sparql endpoint page. On Thu, Jan 22, 2015 at 3:19 PM, Luca Matteis lmatt...@gmail.com wrote: Give me all your types seems the most sensible thing to do. Otherwise full text search. On Thu, Jan 22, 2015 at 3:09 PM, Juan Sequeda juanfeder...@gmail.com wrote: Assume you are given a URL for a SPARQL endpoint. You have no idea what data is being exposed. What do you do to explore that endpoint? What queries do you write? Juan Sequeda +1-575-SEQ-UEDA www.juansequeda.com -- Jerven Bolleman m...@jerven.eu
CFP: 1st International Workshop on Summarizing and Presenting Entities and Ontologies (SumPre 2015)
SumPre 2015 - 1st Call for Papers 1st International Workshop on Summarizing and Presenting Entities and Ontologies co-located with the 12th European Semantic Web Conference May 31 or June 1, 2015, Portorož, Slovenia http://km.aifb.kit.edu/ws/sumpre2015/ OBJECTIVES * The Open Data and Semantic Web efforts have been promoting and facilitating the publication and integration of data from diverse sources, giving rise to a large and increasing volume of machine-readable data available on the Web. Even though such raw data and its ontological schema enable the interoperability among Web applications, problems arise when exposing them to human users, as to how to present such large-scale, structured data in a user-friendly manner. To meet the challenge, we invite research contributions on all aspects of ranking, summarization, visualization, and exploration of entities, ontologies, knowledge bases and Web Data, with a particular focus on their summarization and presentation. We also welcome submissions on novel applications of these techniques. The workshop is expected to be a forum that brings together researchers and practitioners from both academia and industry in the areas of Semantic Web, information retrieval, data engineering, and human-computer interaction, to discuss high-quality research and emerging applications, to exchange ideas and experience, and to identify new opportunities for collaboration. TOPICS OF INTEREST Topics include, but are not limited to, the following: 1) Ranking and summarizing entities, ontologies, knowledge bases and Web data * Entity ranking, summarization, and search * Task and context-specific entity summarization * Summarization of graphs and knowledge bases * Ontology ranking, summarization, modularization, and search * Fact ranking, retrieval, and question answering over the Web * Evaluation of ranking and summarization methods 2) Visualizing and exploring entities, ontologies, knowledge bases and Web data * Verbalizing and visualizing entity-centric data * Ontology visualization and exploration * Navigation, faceted browsing, and exploratory search * Entity/link/ontology recommendation * Novel presentation methods and interaction paradigms for knowledge bases and Web data * User studies with visualization and exploration methods 3) Novel applications of the above techniques IMPORTANT DATES * * Submission deadline: March 6, 2015 (23:59 Hawaii Time) * Notifications: April 3, 2015 (23:59 Hawaii Time) * Camera-ready version: April 17, 2015 (23:59 Hawaii Time) * Workshop day: May 31 or June 1, 2015 SUBMISSIONS *** We seek the following kinds of submissions: * Full research papers: up to 12 pages in Springer LNCS format * Short research/in-use/demo papers: up to 5 pages in Springer LNCS format * Pitch notes (novel/original ideas): up to 2 pages in Springer LNCS format Papers should be submitted in EasyChair: https://easychair.org/conferences/?conf=sumpre2015 Accepted papers will be presented at the workshop and included in a volume of the CEUR workshop proceedings. Best papers will be included in the supplementary proceedings of ESWC 2015, and their extended versions will be recommended to the International Journal on Semantic Web and Information Systems (IJSWIS). At least one author of each accepted paper is expected to register for the workshop and attend to present the paper. STEERING COMMITTEE ** * Sören Auer, University of Bonn, Germany * Amit Sheth, (Kno.e.sis) Wright State University, USA ORGANIZERS * * Gong Cheng, Nanjing University, China * Kalpa Gunaratna, (Kno.e.sis) Wright State University, USA * Andreas Thalhammer, Karlsruhe Institute of Technology (KIT), Germany
RE: How do you explore a SPARQL Endpoint?
Agree with most of these as good exploratory queries, but be very careful of
using the bottom-up approaches on endpoints that you don’t own. These can be
very hard on the endpoint’s triple store. I like Bernard Vatant’s approach of
trying to find a declared data model first. If it’s there, such queries should
not tax the endpoint’s triple store; much less so than large table scans that
the other ones can trigger.
--
Mark Wallace
Principal Engineer, Semantic Applications
MODUS OPERANDI, INC.
From: Nandana Mihindukulasooriya [mailto:nmihi...@fi.upm.es]
Sent: Thursday, January 22, 2015 11:01 AM
To: Bernard Vatant
Cc: Semantic Web; public-lod public
Subject: Re: How do you explore a SPARQL Endpoint?
May be not just looking at the classes and properties but looking at their
frequencies using counts can give a better idea about what sort of data is
exposed. If there is a Void information it certainly helps. Tools such as
http://data.aalto.fi/visu also help. Similar approach described here [1] .
Best Regards,
Nandana
[1] - http://ceur-ws.org/Vol-782/PresuttiEtAl_COLD2011.pdf
On Thu, Jan 22, 2015 at 4:25 PM, Bernard Vatant
bernard.vat...@mondeca.commailto:bernard.vat...@mondeca.com wrote:
Interesting to note that the answers so far are converging towards looking
first for types and predicates, but bottom-up from the data, and not queries
looking for a declared model layer using RDFS or OWL, such as e.g.,
SELECT DISTINCT ?class
WHERE { {?class a owl:Class} UNION {?class a rdfs:Class}}
SELECT DISTINCT ?property ?domain ?range
WHERE { {?property rdfs:domain ?domain} UNION {?property rdfs:range ?range}}
Which means globally you don't think the SPARQL endpoint will expose a formal
model along with the data.
That said, if the model is exposed with the data, the values of rdf:type will
contain e.g., rdfs:Class and owl:Class ...
Of course in the ideal situation where you have an ontology, the following
would bring its elements.
SELECT DISTINCT ?o ?x ?type
WHERE {?x rdf:type ?type.
?x rdfs:isDefinedBy ?o.
?o a owl:Ontology }
It's worth trying, because if the dataset you query is really big, it will be
faster to look first for a declared model than asking all distinct rdf:type
2015-01-22 15:23 GMT+01:00 Alfredo Serafini
ser...@gmail.commailto:ser...@gmail.com:
Hi
the most basic query is the usual query for concepts, something like:
SELECT DISTINCT ?concept
WHERE {
?uri a ?concept.
}
then, given a specific concept, you can infer from the data what are the
predicates/properties for it:
SELECT DISTINCT ?prp
WHERE {
[] ?prp a-concept.
}
and so on...
Apart from other more complex query (here we are of course omitting a lot of
important things), these two patterns are usually the most useful as a
starting point, for me.
2015-01-22 15:09 GMT+01:00 Juan Sequeda
juanfeder...@gmail.commailto:juanfeder...@gmail.com:
Assume you are given a URL for a SPARQL endpoint. You have no idea what data is
being exposed.
What do you do to explore that endpoint? What queries do you write?
Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.comhttp://www.juansequeda.com
--
Bernard Vatant
Vocabularies Data Engineering
Tel : + 33 (0)9 71 48 84 59
Skype : bernard.vatant
http://google.com/+BernardVatant
Mondeca
35 boulevard de Strasbourg 75010 Paris
www.mondeca.comhttp://www.mondeca.com/
Follow us on Twitter : @mondecanewshttp://twitter.com/#%21/mondecanews
--
Deadline extension and 3rd call for papers for SOCM2015 (at WWW2015)
Hi all, The deadline for the 3rd edition of the SOCM workshop was extended to the 1st of February. More details about the workshop topics and submission details in the cfp below and on WikiCfP ( http://www.wikicfp.com/cfp/servlet/event.showcfp?eventid=42299 ) Cheers, Laura -- == 3rd Call for papers == SOCM 2015: Third international workshop on the theory and practice of social machines: observing social machines on the Web @ WWW 2015, Florence, Italy 18 May 2015 http://sociam.org/socm2015/ The 2015 edition of the SOCM workshop will look deeply at social machines that have, or may yet soon have, a profound impact on the lives of individuals, businesses, governments, and the society as a whole. Our goal is to discuss issues pertinent to the observation of both extant and yet unrealized social machines building on work of the previous editions of the SOCM workshop (SOCM2013 and SOCM2014) and the Web Observatory workshops of the last two years (WOW2013 and WOW2014). SOCM2015 aims to identify factors that govern the growth or impede these systems to develop, and to identify unmet observation needs or the kinds of loosely-coordinated distributed social systems the Web enables. We also intend to discuss methods to analyse and explore social machines, as essential mechanisms for deriving the guidelines and best practices that will inform the design of social machines and social machine observatories. Supported by the SOCIAM project (http://sociam.org) === Objectives === The workshop will discuss the latest theoretical frameworks and empirical insights around the observation of social machines. As introduced in the initial edition of the workshop, we use the term social machines to refer to socio-technical systems which leverage the Web as a medium for communication, socialization, decentralized coordination, and peer production. This theme derives from concepts introduced by Tim Berners-Lee in his influential book Weaving the Web, in which he describes the Web as an engine to create abstract social machines - new forms of social processes that would be given to the world at large. Unlike conventional Turing machines, their social counterparts are comprised of loose collectives of people connected by computational communication substrates at their core. By being accessible to any individual with access to the Web, such social machines have demonstrated the ability to allow groups of individuals to accomplish major goals using methods of distributed coordination and crowdsourcing at unprecedented scales. However, the study of such systems also requires a new and fundamentally different set of instruments, which, though inspired by the mindset of Computer Science and Engineering, naturally embraces theories, findings, and scientific methodology from a variety of other disciplines in order to understand how human and machine intelligence could be best brought together to help individuals, businesses, governments and the society. This includes languages and models to describe their function and operation; visualisation of social machine operation and evolution, and methods that can be applied to study and predict their behaviour. The objective of the workshop is to bring together experts of various kinds of social machines, including crowd-powered systems, social networks, and online communities, to discuss the challenges of meaningful observation of social machines and to present specific tools that they have designed to visualise social machines and their impact on the various sectors of human activity. These applications are increasingly employing Web observatory infrastructures for sharing of data, results and methods. === Topics === The workshop proposes a multidisciplinary discussion focused on the following three themes: 1. Analysing social machines: analytics and visualisations that provide insights about social machines and their impact, including: - Quantitative and qualitative aspects of online peer production and information exchange systems (multimedia sharing sites, auction sites, discussion forums, crowdsourced science, gamified customer relationship management, Wikipedia etc). - Visualisation of social machine ecosystems and of social machine operation and evolution. - Studies on the effect of social machines in business, government and society and of mechanisms that they employ to engage the people (incentivisation, motivation). 2. Designing social machine observatories: analyses of the design of effective (extant and future) social machines, including: - Deployment of Web Observatories to study social machines and their ecosystem. - Infrastructural challenges to the observation of complex ecosystems of systems and platforms bringing together social and algorithmic components. - Evaluation and quality assessment techniques of social machine observatories. 3. Methodology and methods: approaches and methods for observing social machines, including: - Languages and models
Re: linked open data and PDF
Wow, there's a blast from the past*. --Gannon * past = back when URL's looked like URI's and control freaks could keep their domain holdings and ontologies on the same ledger. Not for a minute do I think this was a good thing, and in any case no fault of GRDDL. On Wed, 1/21/15, Paul Tyson phty...@sbcglobal.net wrote: Subject: Re: linked open data and PDF To: Norman Gray nor...@astro.gla.ac.uk Cc: Paul Houle ontolo...@gmail.com, Herbert Van de Sompel hvds...@gmail.com, jschnei...@pobox.com jschnei...@pobox.com, public-lod@w3.org public-lod@w3.org Date: Wednesday, January 21, 2015, 8:52 PM On Wed, 2015-01-21 at 17:16 +, Norman Gray wrote: (also it's not even really about XMP; there are all sorts of ways of scraping metadata out of objects and turning it into something which an RDF parser can read, and from that point you can start being imaginative. This is of course stupidly obvious to everyone on this list, but it's an aha! that many people haven't got yet). GRDDL, anyone? [1] I think the GRDDL spec was too narrowly scoped to XML resources. The concept is simple and ingenious, and applicable to any type of resource. Many years ago, inspired by the then-new GRDDL spec) I built a modest RDF gleaning framework for tracing software requirements through development and testing. It gleaned from requirements documents and functional specification (in MS Word format), design documents (in TeX), source code (c++), test results (in XML), and probably also plain text (csv) and MS Excel. Regards, --Paul [1] http://www.w3.org/TR/2007/REC-grddl-20070911/
