[TF-ENT] Agenda 24th Feb teleconf

Hi all,
here is a proposal for the agenda. If you have additional suggestions
or suggestions for amendments, let me know.

   *  Date of Call: Wednesday February 24, 2010
   * Time of Call: 18:00 UK, 13:00 (East US)
   * Dial-In #: +1.617.761.6200 (Cambridge, MA)
   * Dial-In #: + (Nice, France)
   * Dial-In #: +44.117.370.6152 (Bristol, UK)
   * Participant Access Code:
     Zakim will tell us when the ad hoc conference is set up
   * IRC Channel: irc.w3.org port 6665 channel #sparql-ent
   * Duration: 60 minutes
   * Chair: Birte Glimm
   * Scribe: ?
   * Link to Agenda: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

* Admin
  o Do we need a scribe?
* General entailment regimes issues
  o Should we have a finite vocabulary from which bindings can be taken
    for all variables and not just the ones in subject position. This
    allows for defining the scoping graph as graph equivalent to the active
    graph even in the case of an inconsistency and would mean a modified C2
    Current C2 in PWD:
    (C2) Each variable x that occurs in the subject position of a triple in
         BGP is such that sk(μ(x)) occurs in sk(SG).
    Proposed C2:
    (C2) For each variable x in V(BGP), sk(μ(x)) occurs in sk(SG) or in
    Here vocal is defined as the reserved vocabulary for the entailment
    regime (e.g., the RDF vocabulary for RDF entailment) minus terms of the
    form rdf:_n with n in {1, 2, …}.
* RIF issues
  o Will/should RIF be marked as "at risk" depending on the RIF WG note
    about the RIF-to-RDF mapping? What is the status of the RIF to RDF
    mapping? Will there be something like rif:import?
  o Entailment regimes have to define which graphs the accept. Will the RIF
    entailment regime work with all RDF graphs? Different lists in RDF and
  o Will each rule set be an entailment regime, e.g., the SD says something
    like: myEndpoint sd:EntailmentRegime <http://example.org/myRules.rif>?
    Or is there a suitable RIF entailment relation (RIF+RDF semantics) and
    one specifies a rule set in a from clause or in the data set? Which RIF
    profiles does that cover? This might affect the condition on extensions
    to BGP matching that requires that
    SG E-entails (SG union P1(BGP1) union ... union Pn(BGPn))
  o How are blank nodes defined in RIF? Will skolemization/mapping to RIF
    local symbols work as for the other regimes?
  o Not all RIF dialects are based on a model-theory (e.g., RIF PRD), so
    they do not come with an entailment relation, but have a procedural
    semantics. Can we still use the procedural semantics to define
    something like an entailment regime?
  o Which RIF profiles should be included? Only RIF Core? Does RIF Core
    coincide with OWL RDF-Based or Direct Semantics? How many profiles are
  o What effects do the non-monotonic features of some RIF dialects have?
    E.g., RIF PRD and (anticipated) RIF dialects with default negation.
    How does that interact with SPARQL's non-monotonic features?
    This probably affects issue-43: Should entailment-regimes be declared
    over the whole dataset or individual graphs?
  o RIF production rules: it is no even clear how conjunctive queries work.
  o What is our timeline for RIF?

Dr. Birte Glimm, Room 306
Computing Laboratory
Parks Road
United Kingdom
+44 (0)1865 283529

Received on Sunday, 21 February 2010 21:45:56 UTC