- From: Sebastian Samaruga <cognescent@gmail.com>
- Date: Tue, 13 Jan 2015 21:03:50 -0300
- To: "Eric Prud'hommeaux" <eric@w3.org>
- Cc: "semantic-web@w3.org" <semantic-web@w3.org>, "pragmaticweb@lists.spline.inf.fu-berlin.de" <pragmaticweb@lists.spline.inf.fu-berlin.de>
- Message-ID: <CAFnmbpWgZeDKrtxBBsg3QQXqqB1z8qWFSm1ZiPMjduoYsrGwXw@mail.gmail.com>
I've updated the repository and now there is an executable WAR file for testing in servlet containers. There are also the complete sources which haven't been correctly uploaded. Project: https://code.google.com/p/cognescent/ (in source section are instructions for checking out via svn). Best, Sebastian. On Sun, Jan 11, 2015 at 2:24 PM, Sebastian Samaruga <cognescent@gmail.com> wrote: > Yes, is true. I haven't reached at that point yet and I understand that > recording the inferences I make in OWL would be a lot helpful, mostly > because I try to merge diverse sources and also augment knowledge with > linked data and upper ontologies. My reason for haven't using those > features yet is because I only use 'plain' RDF to infer metadata. Only SPO > triples with no schema information are my sources of data. And, once there, > my model allows the assertion of one subject in one role or occurrence to > be referred under some kind of type (or, at least, I try). > > But it will help a lot if, once I infer properties, types and class > restrictions, I put them in OWL so I can reuse them later or use them for > further inference. Thanks a lot for your advice, I'll taking it into > account. And, as I said before, my tools and my skills limit me somehow so > your knowledge is really helpful. > > Best, > Sebastian. > > > On Sun, Jan 11, 2015 at 3:58 AM, Eric Prud'hommeaux <eric@w3.org> wrote: > >> * Sebastian Samaruga <cognescent@gmail.com> [2015-01-10 18:22-0300] >> > Hi, sorry for the delay in the response too. >> > >> > Yes, maybe I'm ambitious. And maybe I don't have all the tools/skills I >> > need at hand when I try to develop or communicate my ideas. >> > >> > I was surprised when someone told that only using RDF Schema is >> possible to >> > infer types. Actually, I'm currently inferring type information on >> > arbitrary sets of entities using only their properties information. >> When I >> > know that many subjects share the same set of properties I can be >> allowed >> > to think that they belong to the same class. And when they share the >> same >> > values for their properties, I can infer they are in a similar 'state' >> > (i.e.: single / married, student / employee, etc). >> >> Minor (perhaps orthogonal) point: RDFS doesn't enable one to infer >> types in the sense that you are using; it simply has some rules used >> to infer types, e.g. >> { W <p1> X . <p1> rdfs:domain Y . } implies { W rdf:type Y } . >> { W <p1> X . <p1> rdfs:range Z . } implies { X rdf:type Z } . >> >> OWL enables you write nuanced rules, e.g. every X of type Doctor who >> is treating some patient most also be a PracticingDoctor. This may >> address some of the "context" which Pat warned you about below by >> capturing the constraints for that context in a computable structure. >> >> If you know in advance the properties you are examining and the >> criteria for inferring types, you can probably record most of that in >> OWL. If your process examines a graph and clusters nodes based on >> similarity, (perhaps with some human oversight looking at the >> instances to say "I'll call those PracticingDoctors", you can probably >> record those discovered criteria in OWL. >> >> Take a peek at the OWL primer to see if it applies to your work >> <http://www.w3.org/TR/owl2-primer/>. Note that >> <http://www.w3.org/TR/owl2-primer/#OWL_Syntaxes> provides a switch for >> what languages are displayed; for this forum, turtle syntax will reach >> the broadest audience. >> >> >> > Using RDF as the core format where many data sources converge, and this >> > kind of metadata information from the RDF I'll try to observe >> 'Concepts' to >> > which classes/types belong. It's a kind of role or meta class where some >> > instances of Things are classified. Things are abstract subjects of >> > discurse of what references or Signs can be made of. For example, Woody >> > Allen has an occurrence (manifestation of existence) as the director >> > (concept / role) of some movie (another Thing). >> > >> > The goal is to be able to take note of all of those relationships in a >> kind >> > of index where equivalences between different sources of data talking >> about >> > the same subjects, in a different vocabulary, can be deduced. This is >> the >> > intention of many Semantic Web projects already, and this metadata >> > (de)aggregation would benefit a lot from linked data sources. >> > >> > Luckily I could develop an (ongoing) proof of concept project of what I >> > propose, which I'm hosting at googlecode: >> > >> > https://code.google.com/p/cognescent/ (checkout sources only in the CBI >> > folder) >> > >> > It's a Java Web Application project with instructions in how to exec in >> the >> > README. It's a work in progress. It provides an OData frontend, browse >> > service document, instances and metadata, all from any RDF datasource. >> It >> > can also be configured to use a relational database modifying Main.java >> > manually (for now). It translates the relational data to RDF to perform >> > model set up. >> > >> > Best regards, >> > Sebastian. >> > >> > >> > On Fri, Oct 10, 2014 at 10:20 AM, Thierry BIARD, EIRL AMBESAS < >> > thierry.ambesas@gmail.com> wrote: >> > >> > > Hi Sebastian, >> > > >> > > >> > > >> > > I hope you are fine. Sorry for the delay of response. As far as RDF is >> > > concerned, I am not good enough to discuss this matter. I suppose >> that Pat >> > > Hayes is an expert and that his comments are relevant and will help >> you on >> > > your ambitious demarche. You are not of those who give up. I know >> that you >> > > will continue. >> > > >> > > >> > > >> > > Best regards. >> > > >> > > >> > > >> > > Thierry >> > > >> > > >> > > >> > > *De :* Sebastian Samaruga [mailto:cognescent@gmail.com] >> > > *Envoyé :* mercredi 17 septembre 2014 19:55 >> > > *À :* Pat Hayes >> > > *Cc :* Thierry BIARD, EIRL AMBESAS; semantic-web@w3.org; >> > > pragmaticweb@lists.spline.inf.fu-berlin.de >> > > *Objet :* Re: Micellaneous >> > > >> > > >> > > >> > > Ok, I should have stated that this is intended to build an API in some >> > > language to perform the mentioned operations. >> > > >> > > Aggregating URIs means that if they occur multiple times in a closed >> world >> > > model in which I know all the statements then I can be sure that they >> > > represent the same thing. Another task of a given ETL tool could be >> perform >> > > merging and mapping of some kind, maybe to an upper ontology to >> facilitate >> > > this task. >> > > >> > > The algorithm for types is there and it is working. Those are inferred >> > > types and as in the previous paragraph I suppose a closed world like, >> for >> > > example, and RDF dump of a relational database. This closed world >> > > assumption can be relaxed having the possibility of merging multiple >> > > documents in the ETL component. >> > > >> > > Methods and contexts refer to the to be implemented API. Sorry for >> not be >> > > clear enouth about that. And Resource class methods (getXXX) receive >> the >> > > context as their arguments which can be one of the tree possible >> arguments >> > > listed. Subclasses (Concept, Thing, Sign) may override this behavior.. >> > > >> > > Best, >> > > Sebastian Samaruga. >> > > >> > > >> > > >> > > On Wed, Sep 17, 2014 at 2:13 PM, Pat Hayes <phayes@ihmc.us> wrote: >> > > >> > > >> > > On Sep 17, 2014, at 9:30 AM, Sebastian Samaruga <cognescent@gmail.com >> > >> > > wrote: >> > > >> > > > Thierry, thanks really for your time answering my emails. I didn't >> take >> > > the online course. Although I've spending some of my time in some >> kind of >> > > semantic (semiotic) metamodel for what I understand as knowledge >> > > representation.. >> > > > >> > > > I'm copying this mail to the liists. >> > > > >> > > > For what I came with, the core concepts, borrowed from semiotics, >> are: >> > > > 1. Concept >> > > > 2. Thing >> > > > 3. Sign >> > > > >> > > > First, a Sign is an occurrence of a Thing in some context. For >> example, >> > > in RDF, some URI referring something that somehow exist. >> > > > >> > > > A Thing is something that can exist and, given that notion, can >> appear >> > > in occurrences of some kind. A thing also aggregates all of its >> occurrences >> > > as they represent the Thing as a whole. >> > > > >> > > > Finally, a Concept is an abstraction of a set of Things. Things are >> > > instances of Concepts and, again, which Concept they are instance of >> is >> > > context dependent. A Thing could be regarded as an occurrence of a >> Concept. >> > > > >> > > > So, given that I begin with Things and I need a source of them I can >> > > begin with some RDF source without the need of any schema embedded in >> it. >> > > The URIs in the triples are Signs. >> > > >> > > OK so far, although RDF does not support contexts, so a given IRI is >> > > assumed to denote the same thing everywhere it occurs. >> > > >> > > > Aggregating all occurrences of the same URI I came up with the Thing >> > > they represent. >> > > >> > > ? How does that work? What do you mean by 'aggregating'? And how can >> you >> > > know if you have all the occurrences of a given IRI, on the entire >> Web? >> > > (You can't possibly know this.) >> > > >> > > > Then using a simple algorithm of which URIs share the same >> predicates I >> > > can infer the type of the URIs and came up with the Concepts. >> > > >> > > That is not going to work, because you would also need to know the >> domain >> > > and range properties of those predicates, and that information is not >> > > always given explicitly. At the very least, you will need RDFS or OWL >> type >> > > reasoning here. >> > > >> > > > >> > > > Now, the meta model: >> > > > The core concepts inherits from a Resource class. This parent class >> has >> > > the following methods: >> > > >> > > "methods"? That term is not meaningful in RDF. >> > > >> > > > >> > > > Resource::getSigns(Sign | Thing | Concept) : Occurrences of argument >> > > > Resource::getThings(Sign | Thing | Concept) : Instances of argument >> > > > Resource::getConcepts(Sign | Thing | Concept) : Classes / roles of >> > > argument. >> > > > >> > > > Example data: >> > > > aPerson :employment anEmployment (Signs) >> > > > Peter :employment SalesDptManager (Thiings) >> > > > Person, Employe :employment Employment, Position (Concepts) >> > > > >> > > > So, care must be taken building an ETL RDF tool that populates this >> > > bindings in Resource instances, provides querying facilities and >> support >> > > the construction of entities which apply rules-transformation kind of >> > > behavior using 'template' resources. >> > > > >> > > > Then the model should allow to build queries navigating Resource >> APIs >> > > like retrieving all the Concepts a Thing plays in a context, which >> Signs >> > > are instances of a given Thing in a given Concept context, etc. >> > > >> > > To repeat, there are no contexts in RDF. >> > > >> > > I would strongly recommend that you read more about RDF and its >> intended >> > > semantics before proceeding. >> > > >> > > Best wishes >> > > >> > > Pat Hayes >> > > >> > > > >> > > > Best, >> > > > Sebastian Samaruga.. >> > > > >> > > >> > > ------------------------------------------------------------ >> > > IHMC (850)434 8903 home >> > > 40 South Alcaniz St. (850)202 4416 office >> > > Pensacola (850)202 4440 fax >> > > FL 32502 (850)291 0667 mobile >> (preferred) >> > > phayes@ihmc.us http://www.ihmc.us/users/phayes >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> >> -- >> -ericP >> >> office: +1.617.599.3509 >> mobile: +33.6.80.80.35.59 >> >> (eric@w3.org) >> Feel free to forward this message to any list for any purpose other than >> email address distribution. >> >> There are subtle nuances encoded in font variation and clever layout >> which can only be seen by printing this message on high-clay paper. >> > >
Received on Wednesday, 14 January 2015 00:04:56 UTC