René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Additional links displayed in Relfinder + test case","articleBody":"```\nHi, there was a post on the apache stanbol list, which provides a test case. I \nposted it below and attached the screenshot. The triples are missing from the \nRDF, I checked this, but I didn't reproduce the error. \nAll the best,\nSebastian\n\n\n\nHi Sebastian, \n\nI finally managed some more time to work on this. I've run into good and bad \nnews: the good news is that sometimes RelFinder will find non-trivial paths \n(something more complicated than \"a and b both have some relationship to c\") \nbut the results are somewhat wonky and I don't think it finds all of them that \nit should. See the end of this email for the example RDF data that I'm using.\n\n    This query correctly returns document-1 when executed on the Stanbol SPARQL endpoint:\nSELECT * WHERE {\n?middle ?pf1 \u003chttp://some.org/people/person-1\u003e  . \n?middle ?ps1 \u003chttp://some.org/people/person-2\u003e  . \n} LIMIT 10\n\n    And the following query correctly returns document-2\nSELECT * WHERE {\n?middle ?pf1 \u003chttp://some.org/people/person-2\u003e  . \n?middle ?ps1 \u003chttp://some.org/people/person-3\u003e  . \n} LIMIT 10\n\n   The following query also works, however, I don't see it as one of the Relfinder queries specified in [1]:\nSELECT * WHERE {\n?middle ?pf1 \u003chttp://some.org/people/person-1\u003e . \n?os1 ?ps1 \u003chttp://some.org/people/person-3\u003e . \n?os1 ?ps2 ?os2 . \n?middle ?ps3 ?os2 . \n} LIMIT 10\n\nShould the above query be included in Relfinder for max relation lengths \u003e 4, \nand if so, any tips on how to modify relfinder? As it stands, the RDF DATA \nVERSION 1 does have a path connecting persons 1 and 3, but Relfinder doesn't \nfind it.\n\nAlso, if I modify the rdf data to include inverse author properties (see RDF \nDATA VERSION 2) then RelFinder correctly finds the path through the document \nfrom person 1 to person 3, but starts adding spurious links when I search \nbetween person 1 and person 2. For instance, it includes author and creator \narrows going both ways, like document 1 -\u003e creator -\u003e person2 AND document1 -\u003e \nauthor -\u003e person 2. The last statement isn't correct and isn't included in the \nRDF. I've attached a screenshot.\n\n[1] \nhttp://dbpedia.aksw.org/dbpedia_demo/dbpedia/tutorials/relfinder_search/demo_rel\nfinder.php\n\nRDF DATA VERSION 1:\n\u003c?xml version=\"1.0\" encoding=\"UTF-8\"?\u003e\n\u003crdf:RDF\n    xmlns:rdfs=\"http://www.w3.org/2000/01/rdf-schema#\"\n    xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"\n  xmlns:dcterms=\"http://purl.org/dc/terms/\"\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-2\"\u003e\n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003crdfs:label\u003ePerson 2\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-3\"\u003e\n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003crdfs:label\u003ePerson 3\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-1\"\u003e\n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003crdfs:label\u003ePerson 1\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/documents/document-1\"\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-1\"/\u003e\n    \u003crdfs:label\u003eDocument 1\u003c/rdfs:label\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-2\"/\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/documents/document-2\"\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-3\"/\u003e\n    \u003crdfs:label\u003eDocument 2\u003c/rdfs:label\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-2\"/\u003e\n\u003c/rdf:Description\u003e\n\n\u003c/rdf:RDF\u003e\n\nRDF DATA VERSION 2\n\u003c?xml version=\"1.0\" encoding=\"UTF-8\"?\u003e\n\u003crdf:RDF\n    xmlns:rdfs=\"http://www.w3.org/2000/01/rdf-schema#\"\n    xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"\n    xmlns:dcterms=\"http://purl.org/dc/terms/\"\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-2\"\u003e\n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003cdcterms:author rdf:resource=\"http://some.org/documents/document-1\"/\u003e\n    \u003cdcterms:author rdf:resource=\"http://some.org/documents/document-2\"/\u003e\n    \u003crdfs:label\u003ePerson 2\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-3\"\u003e\n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003cdcterms:author rdf:resource=\"http://some.org/documents/document-3\"/\u003e \n    \u003crdfs:label\u003ePerson 3\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/people/person-1\"\u003e\n    \u003cdcterms:author rdf:resource=\"http://some.org/documents/document-1\"/\u003e \n    \u003crdf:type rdf:resource=\"http://xmlns.com/foaf/0.1/Person\"/\u003e\n    \u003crdfs:label\u003ePerson 1\u003c/rdfs:label\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/documents/document-1\"\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-1\"/\u003e\n    \u003crdfs:label\u003eDocument 1\u003c/rdfs:label\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-2\"/\u003e\n\u003c/rdf:Description\u003e\n\n\u003crdf:Description rdf:about=\"http://some.org/documents/document-2\"\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-3\"/\u003e\n    \u003crdfs:label\u003eDocument 2\u003c/rdfs:label\u003e\n    \u003cdcterms:creator rdf:resource=\"http://some.org/people/person-2\"/\u003e\n\u003c/rdf:Description\u003e\n\n\u003c/rdf:RDF\u003e\n\n\n```\n\nOriginal issue reported on code.google.com by `kur...@googlemail.com` on 27 Jun 2013 at 6:23\n","author":{"url":"https://github.com/GoogleCodeExporter","@type":"Person","name":"GoogleCodeExporter"},"datePublished":"2015-12-05T12:51:17.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/50/RelFinder/issues/50"}