RulesReasoningLP: mini-series session-03 - Thu 2013-11-21    (3ZUX)

Program: Ontology, Rules, and Logic Programming for Reasoning and Applications (RulesReasoningLP) mini-series of virtual panel sessions    (41EW)

Topic: Concepts and Foundations of Rules and Ontologies: Logic Programs, Classical Logic, and Semantic Web - II    (3ZUY)

Session Co-chairs: Dr. Leo Obrst (Ontolog; MITRE) & Professor Pascal Hitzler (Wright State U) ... intro slides    (3ZUZ)

Panelists / Briefings:    (3ZV0)

Archives:    (3ZV5)

Conference Call Details:    (3ZVE)

Attendees:    (3ZWC)

Abstract    (3ZWR)

Concepts and Foundations of Rules and Ontologies: Logic Programs, Classical Logic, and Semantic Web - II ... intro slides    (3ZWS)

This is the 3rd session of the RulesReasoningLP mini-series - a series of virtual panel sessions, and the associated online discourse, co-championed by some members of the Ontolog community who value the importance of the subject matter and would want to bring together those who are knowledgeable or interested into a dialog. The mini-series program will cover the topics that encapsulates the ontology-driven applications that will generally fall under "Ontology, Rules, and Logic Programming for Reasoning and Applications."    (412K)

This session is the second of two sessions devoted to addressing the concepts and foundations of the technologies underlying ontology and rule reasoning, especially focused on logic programming and Semantic Web extensions. Panelists invited to share their work with us today include Dr. MarkusKroetzsch, Dr. HectorPerezUrbina, Professor HassanAitKaci and Professor EnricoFranconi.    (412L)

After the panelists briefings, there will be time for Q&A and an open discussion among the panel and all the participants.    (412M)

See more details at: RulesReasoningLP (homepage for this mini-series)    (412N)

Briefings:    (3ZWU)

Agenda:    (412W)

RulesReasoningLP Mini-series Panel Session-03    (412X)

Session Format: this is a virtual session conducted over an augmented conference call    (412Y)

Proceedings    (3ZWT)

Please refer to the above    (4134)

IM Chat Transcript captured during the session:    (4135)

 see raw transcript here.    (4136)
 (for better clarity, the version below is a re-organized and lightly edited chat-transcript.)
 Participants are welcome to make light edits to their own contributions as they see fit.    (4137)
 -- begin in-session chat-transcript --    (4138)
	------
	Chat transcript from room: ontolog_20131121
	2013-11-21 GMT-08:00 [PST]
	------    (41FR)
	[9:03] PeterYim: Welcome to the    (41FS)
	 = RulesReasoningLP: mini-series session-03 - Thu 2013-11-21 =    (41FT)
	Program: Ontology, Rules, and Logic Programming for Reasoning and Applications (RulesReasoningLP) 
	         Mini-series of virtual panel sessions    (41FU)
	Topic: Concepts and Foundations of Rules and Ontologies: Logic Programs, Classical Logic, and Semantic Web - II    (41FV)
	Session Co-chairs: Dr. LeoObrst (Ontolog; MITRE) & Professor PascalHitzler (Wright State U)    (41FW)
	Panelists / Briefings:    (41FX)
	* Dr. MarkusKroetzsch (Technische Universität Dresden) - "Existential Rules in Ontological Modelling"    (41FY)
	* Dr. HectorPerezUrbina (Clark & Parsia, LLC) - "Modeling with Rules in Practice"    (41FZ)
	* Professor HassanAitKaci (Université Claude Bernard Lyon 1) - "Reasoning and the Semantic Web"    (41G0)
	* Professor EnricoFranconi (Free University of Bozen-Bolzano) - "The Logic of Extensional RDFS"    (41G1)
	Logistics:    (41G2)
	* Refer to details on session page at: http://ontolog.cim3.net/cgi-bin/wiki.pl?ConferenceCall_2013_10_31    (41G3)
	* (if you haven't already done so) please click on "settings" (top center) and morph from "anonymous" to your RealName    (41G4)
	* Mute control (phone keypad): *7 to un-mute ... *6 to mute    (41G5)
	* Attn: Skype users ... see: http://ontolog.cim3.net/cgi-bin/wiki.pl?ConferenceCall_2013_11_21#nid3ZVN
	** you may connect to (the skypeID) "joinconference" whether or not it indicates that it is online 
	   (i.e. even if it says it is "offline," you should still be able to connect to it.)
	** if you are using skype and the connection to "joinconference" is not holding up, try using (your favorite POTS or 
	   VoIP line, etc.) either your phone, skype-out or google-voice and call the US dial-in number: +1 (206) 402-0100 
	   ... when prompted enter Conference ID: 141184#
	** Can't find Skype Dial pad?
	*** for Windows Skype users: Can't find Skype Dial pad? ... it's under the "Call" dropdown menu as "Show Dial pad"
	*** for Linux Skype users: please stay with (or downgrade to) Skype version 2.x for now (as a Dial pad seems to be 
	    missing on Linux-based Skype v4.x for skype-calls.)    (41G6)
	Attendees: AidaGandara, AlanRector, AliHashemi, AmandaVizedom, BrandonWhitehead, ChuckRehberg, 
	ConradBock, DavidMendes, DennisWisnosky, DennisPierson, EnricoFranconi, ElieAbiLahoud, 
	FrancescaQuattri, GaryGannon, GenZou, HaroldBoley, HassanAitKaci, HectorPerezUrbina, HensonGraves, 
	JackRing, LamarHenderson, LeoObrst, MarkusKroetzsch, MichaelGruninger, MikeBennett, NaicongLi, 
	NancyWiegand, OliverKutz, OnnoPaap, PascalHitzler, PatrickMaroney, PeterYim, RichardMartin, 
	RyanHohimer, SimonSpero, TaraAthan, ToddPehle, ...    (41G7)
	 == Proceedings ==    (41G8)
	[9:16] anonymous morphed into BrandonWhitehead    (41G9)
	[9:23] anonymous1 morphed into HectorPerezUrbina    (41GA)
	[9:23] anonymous1 morphed into EnricoFranconi    (41GB)
	[9:26] anonymous morphed into EnricoFranconi    (41GC)
	[9:29] anonymous morphed into MarkusKroetzsch    (41GD)
	[9:30] BrandonWhitehead: [in response to PeterYim's appreciation that BrandonWhitehead is joining us from 
	New Zealand, at a very inconvenient hour] Thanks Peter! It's better now...I much prefer 0630 to 0530. :)    (41GE)
	[9:30] anonymous morphed into ElieAbiLahoud    (41GF)
	[9:33] anonymous morphed into PascalHitzler    (41GG)
	[9:35] Hector Perez-Urbina morphed into HectorPerezUrbina    (41GH)
	[9:36] PascalHitzler: Apologies I'm having technical issues with the connection    (41GI)
	[9:40] PascalHitzler: let me try to reconnect    (41GJ)
	[9:41] PascalHitzler: perhaps to avoid further loss of time    (41GK)
	[9:42] PascalHitzler: Leo can make an intro    (41GL)
	[9:42] PascalHitzler: and you can start?    (41GM)
	[9:42] anonymous morphed into ConradBock    (41GN)
	[9:43] PeterYim: == LeoObrst & PascalHitzler starts the session - see slides under 
	http://ontolog.cim3.net/cgi-bin/wiki.pl?ConferenceCall_2013_11_21#nid3ZV8    (41GO)
	[9:46] anonymous morphed into OnnoPaap    (41GP)
	[9:46] PeterYim: == MarkusKroetzsch presenting ...    (41GQ)
	[9:48] anonymous morphed into ChuckRehberg    (41GR)
	[9:51] PeterYim: @Leo @Pascal - we have 37 people on the voice bridge, but only 26 in the chat-room 
	now; so, at the next opportunity (transition to next speaker,) please prompt people to join us in 
	the chat room    (41GS)
	[9:54] anonymous morphed into DavidMendes    (41GT)
	[9:54] AmandaVizedom: @MarkusKroetzsch -- In ontological modeling of complex structures and domains, 
	a classic approach (in AI applications but not DL traditions, of course) is to model many of the 
	relatively stable complex relationships between things *as rules*. To me, it seems that removing 
	rules *as a means of representing complex relationships* from the ontological toolkit makes ontology 
	work much harder and less effective. So, to me, these views seem to overlap. Do you not agree? Or do 
	you think that the complex relationships that exist are not to be ontologically (and declaratively) 
	modeled, or should be modeled in some other way?    (41GU)
	[9:57] AmandaVizedom: @MarkusKroetzsch - the above comment/question was a reaction to your slide 2; I 
	see on slide 6 that you begin to address this.    (41GV)
	[9:59] PascalHitzler: @AmandaVizedom: I'm not Markus, of course, but let me add my own perspective 
	here: The paradigms recently seem to be converging, and in particular work done and initiated by 
	Markus is central for this convergence. Perhaps a good starting point for looking into this is 
	MarkusKroetzsch, Frederick Maier, Adila Alfa Krisnadhi, PascalHitzler, A Better Uncle For OWL - 
	Nominal Schemas for Integrating Rules and Ontologies. In: S. Sadagopan, Krithi Ramamritham, Arun 
	Kumar, M.P. Ravindra, Elisa Bertino, Ravi Kumar (eds.), WWW '11 20th International World Wide Web 
	Conference, Hyderabad, India, March / April 2011. ACM, New York, 2011, pp. 645-654. 
	... see: http://korrekt.org/page/A_Better_Uncle_For_OWL    (41GW)
	[9:58] MichaelGruninger: Speaking controversially, there are many people who equate ontologies with 
	logical theories which are definable in OWL or RDF, and for such people, anything expressed with 
	rules is something that is outside any ontology. Hopefully, this Ontolog mini-series will dispel 
	this misconception.    (41GX)
	[9:59] SimonSpero: If you look at some of the gene and phenotype ontologies, the force fitting into 
	DL for reactions, enzymes etc is especially noticeable    (41GY)
	[10:00] PascalHitzler: @MichaelGruninger: I very much agree :)    (41GZ)
	[10:00] AmandaVizedom: +1 for dispelling that. I'm aware of it, and am happy to acknowledge that as 
	a choice people can make in the type of ontology they work with, but it is frustrating to see people 
	re-define ontology so as to exclude much of its historical and continuing development and application!    (41H0)
	[10:18] MarkusKroetzsch: @MichaelGruninger: "many people [...] equate ontologies with logical 
	theories which are definable in OWL" I have not witnessed this a lot. At least the Description Logic 
	community is quite open to this (the work I mentioned was presented at DL workshop even). I would 
	not call Existential Rules a type of Description Logic, but calling them an ontology language seems fine.    (41H1)
	[10:19] EnricoFranconi: @Markus: +1    (41H2)
	[10:01] SimonSpero: @michaelgruninger: that's not real world controversial, let alone Toronto :-)    (41H3)
	[10:00] anonymous morphed into AidaGandara    (41H4)
	[10:01] anonymous morphed into NaicongLi    (41H5)
	[10:02] PascalHitzler: I freely admit that I'm usually using rules when modeling OWL. Or more 
	precisely, I start with writing rules (which is easier for my brain), or some hybrid (informal) 
	rules/DL notation and then convert them to OWL.    (41H6)
	[10:07] AmandaVizedom: Pascal, when have worked in OWL, I do the same thing. Having academic logic 
	training, then beginning my work in applied ontology with 6 years working in CycL, I also find it 
	much easier to my brain to come up with rules. Translation follows, though sometimes it is not 
	feasible in a given OWL/ application infrastructure and some of the knowledge available for semantic 
	capture simply gets left out. Sometimes that's OK. Sometimes it entails reuse problems down the 
	road.    (41H7)
	[10:02] HectorPerezUrbina: @AmandaVizedom, I found this paper particularly helpful: 
	http://www.cs.ox.ac.uk/boris.motik/pubs/mr10mknf-rules.pdf    (41H8)
	[10:04] AmandaVizedom: Thanks, @Hector. Reconciliation, hmmm. :-)    (41H9)
	[10:06] PascalHitzler: Boris' paper is a landmark. There's some work tightening the integration 
	which follows up on this, e.g. Matthias Knorr, PascalHitzler, Frederick Maier, Reconciling OWL and 
	Non-monotonic Rules for the Semantic Web. In: De Raedt, L., Bessiere, C., Dubois, D., Doherty, P., 
	Frasconi, P., Heintz, F., Lucas, P. (eds.), ECAI 2012, 20th European Conference on Artificial 
	Intelligence, 27-31 August 2012, Montpellier, France. Frontiers in Artificial Intelligence and 
	Applications, Vol. 242, IOS Press, Amsterdam, 2012, pp. 474-479. 
	http://knoesis.wright.edu/faculty/pascal/pub/KHM-ECAI12.pdf    (41HA)
	[10:01] EnricoFranconi: (A technical question: is VNC up? I can't connect)    (41HB)
	[10:02] PascalHitzler: @EnricoFranconi: I'm using VNC, so it's working for me    (41HC)
	[10:02] PeterYim: @EnricoFranconi - don't worry, some people cannot connect properly to the vnc 
	server ... just use you local slides, and remember to prompt slide advances and the slide number verbally    (41HD)
	[10:02] EnricoFranconi: ok, thanx    (41HE)
	[10:06] MichaelGruninger: @MarkusKroetzsch: Are the rules used in the chemistry example on slide 12 
	available online?    (41HF)
	[10:08] PeterYim: == HectorPerezUrbina presenting ...    (41HG)
	[10:08] MarkusKroetzsch is trying to catch up with the chat now ...    (41HH)
	[10:09] AmandaVizedom: @MarkusKroetzsch: By no tools / libraries, did you mean no *open source* 
	tools libraries? I agree with the latter but not the former, obviously.    (41HI)
	[10:16] MarkusKroetzsch: @AmandaVizedom: I mainly meant that the rule-related tools/libraries world 
	is quite fragmented. There is RIF, which I am not aware of libraries for. Almost all reasoners that 
	can handle Datalog and its extensions are from the ASP and LP world, using some (more or less 
	uniform) Prolog-style syntax, which I don't know how to specify datatypes and URI-based identifiers 
	in. The ontology world has SWRL but the tools that support this are AFAIK not happy with some 80k 
	rules as in my example. And LP tools do not support SWRL or RIF syntax.    (41HJ)
	[10:10] PascalHitzler: @AmandaVizedom: For me, the cases where we're *not* able to make the 
	transformation into OWL, are particularly interesting (as a researcher). They point towards 
	limitations of the OWL standard which are worthwhile to work on in attempts to overcome them :)    (41HK)
	[10:11] AmandaVizedom: @Pascal: I agree! I also think that research to identify the patterns of 
	these cases would be both interesting and valuable. The value I'm thinking of is particularly in the 
	area of guidance for choosing ontology types for particular uses.    (41HL)
	[10:10] anonymous morphed into RyanHohimer    (41HM)
	[10:11] EnricoFranconi: I guess that the real challenge with rules as an ontology language is their 
	integration with more classical FOL-based ontology languages (such as OWL and stuff). Obvious 
	mismatches, as already noticed, are closed vs open world assumption, standard/unique name 
	assumption, active domains, etc.    (41HN)
	[10:12] AliHashemi: Is this non-standard language. Or OWL-centric thinking? Axioms don't have 
	variables? I guess it's a very specific notion of axiom?    (41HO)
	[10:13] MichaelGruninger: @EnricoFranconi: You comment implies that you are assuming that rules are 
	necessarily nonmonotonic. One can also consider rules to simply be a syntactic restriction with a 
	monotonic semantics.    (41HP)
	[10:13] AmandaVizedom: @EnricoFranconi: Do you mean rules in a particular syntax? I ask because 
	classical and current ontology languages that are based on FOL or HOL of course have rule 
	representation (and use) as an integral part of them.    (41HQ)
	[10:14] HaroldBoley: RE Slide 4: SWRL can also be serialized in RuleML/XML (rather than in RDF/XML).    (41HR)
	[10:15] HaroldBoley: http://www.w3.org/Submission/SWRL/#5.1    (41HS)
	[11:02] HectorPerezUrbina: @Harold, I've just seen your comments; thank you very much for your pointers.    (41HT)
	[10:15] EnricoFranconi: @Hector: why are you ignoring the W3C standard RIF syntax? 
	http://www.w3.org/2005/rules/wiki/Primer    (41HU)
	[10:17] AmandaVizedom: Regarding Open / Closed World -- it's also worth noting that it is not 
	necessary that a *language* make an open/closed world commitment. IMHO, this is more properly 
	something that characterizes reasoning -- an inference parameter. And it can be treated that way, by 
	supporting explicit declaration: either in an ontology module, stating that it should be interpreted 
	with OW or CW, or in an application or particular query.    (41HV)
	[10:18] HassanAitKaci: Good point Amanda. But which would the default be?    (41HW)
	[10:18] EnricoFranconi: @AmandaVizedom: Open / Closed World assumption regards the semantics of the 
	data! The different languages (and their reasoners) that operate on the data have to respect their 
	meaning, and adopt the right assumption.    (41HX)
	[10:24] AmandaVizedom: @EnricoFranconi: Some models made such assumptions and some don't. I 
	absolutely agree that when they do, it needs to be explicit. That is why I say that it is important 
	to be able to make explicit that a particular ontology/module (or even rule) has one or the other 
	assumption as part of its semantics.    (41HY)
	[10:27] EnricoFranconi: I insist that CWA/OWA (Closed World Assumption / Open World Assumption) is a 
	property of your data: either we know all of your children or only the ones I'm certain about. I can 
	not use an OWA reasoner on top of some data which states complete knowledge about children, say. Or 
	I can not use a CWA reasoner if the data I have is incomplete. We had an extensive discussion on 
	this at last year ISWC: Peter F. Patel-Schneider and Enrico Franconi. Ontology constraints in 
	incomplete and complete data. In ISWC 2012 - 11th International Semantic Web Conference, volume 7649 
	of Lecture Notes in Computer Science, pages 444459. Springer-Verlag, 2012.    (41HZ)
	[10:20] AmandaVizedom: @MarkusKroetzsch: Very true in the OSS and for standard languages. This is 
	IMHO a critical problem. The tools, and considerable integrated support, exist in proprietary 
	software and languages. We need them in the open standard-based world, too.    (41I0)
	[10:21] ConradBock: Maybe tools could let users know when they go outside profiles as they enter rules.    (41I1)
	[10:22] MarkusKroetzsch: @AmandaVizedom: Are there specific closed tools and standards you are 
	thinking about? I recall how the RIF Working Group decided to ignore the ISO Prolog standard because 
	most group members had no access to this closed standard. But many Prolog tools are free.    (41I2)
	[10:27] AmandaVizedom: @Markus: CycL / the Cyc system have the most comprehensive support for all of 
	this that I have worked with. However, I've also worked with a number of organizations that have 
	developed their own KR language and tools, for internal use, that have some subset of these thing 
	that fit what they need for their application type(s) and typical domain problem.    (41I3)
	[10:22] SimonSpero: @HassanAitKaci: CWA/OWA in Cyc is configurable on a per predicate basis, with 
	NAF (negation as failure) settable on per query basis with default of off    (41I4)
	[10:23] HassanAitKaci: @SimonSpero - good for Cyc then ...    (41I5)
	[10:31] PeterYim: == HassanAitKaci presenting ...    (41I6)
	[10:31] HaroldBoley: The relational SWRL Built-Ins were complemented by the functional RIF 
	Built-Ins.    (41I7)
	[10:31] HaroldBoley: http://www.w3.org/TR/rif-dtb/    (41I8)
	[10:32] AmandaVizedom: @EnricoFranconi: In domains in which the data are almost always incomplete, 
	it is quite common to want to reason with that unknownness explicit in some contexts and for other 
	purposes to reason as if (some of) the data were complete, to explore hypotheses and possibilities. 
	Again, why do you think that when it is a property of the data, it cannot be simply stated and 
	reasoned on appropriately? Why make that a fixed feature of a language or reasoner instead?    (41I9)
	[10:35] HectorPerezUrbina: @Amanda, suppose you want to enforce that every instance of the class 
	Employee in your ontology has to have a SSN; under OWA, we couldn't enforce this. We'd have to 
	resort to CWA to be able to find this kind of violation. However, on the other hand, I would still 
	want to infer (under open world) that all employees are people.    (41IA)
	[10:35] HectorPerezUrbina: As Enrico says, whether you want to use OWA or CWA, depends on the nature 
	of your data, regardless of the specific formalism you're using to model it    (41IB)
	[10:36] EnricoFranconi: Well, what I'm saying is that you may want to consider your *data* open or 
	closed - the choice is up to you . BUT you should never use different assumptions at the same time 
	over the same set of data.    (41IC)
	[10:36] MarkusKroetzsch: @HectorPerezUrbina: ... and on the context (the same data might be OWA when 
	viewed as an ontology and CWA when viewed as a list of axioms that I want to search through)    (41ID)
	[10:36] MarkusKroetzsch: @AmandaVizedom: Can you recommend any references on the CWA/OWA combination 
	that you refer to?    (41IE)
	[10:37] HectorPerezUrbina: oh, I disagree. Using the previous example, you could first use OWA to 
	infer that Hector is an Employee, and then CWA to determine that, since Hector doesn't have a SSN, 
	the ontology is invalid.    (41IF)
	[10:37] AmandaVizedom: @Hector, of the data *and* of the reasoning you want to do, no? Again, I'm 
	not arguing that the assumptions should be ignored; I'm arguing that they should be explicitly 
	statable and the reasoners should be able to understand that and use it.    (41IG)
	[10:37] SimonSpero: @EnricoFranconi: agree if it's just assumptions that you're talking about - if 
	an epistemic axiom is asserted, then it stops being an assumption    (41IH)
	[10:38] SimonSpero: Driveby coverage in 12.8 of 
	http://download.springer.com/static/pdf/413/bok%253A978-90-481-8847-5.pdf?auth66=1385231714_9584f2c63627ff5bd4692a4020bf3d52&ext=.pdf    (41II)
	[10:39] AmandaVizedom: @Hector: Your constraint-violation case is an excellent example of a common 
	use case that comes up with OWL ontologies. when you are looking for (potential) violations, you may 
	want to temporarily use CWA, rather than use OWA and infer missing statements.    (41IJ)
	[10:40] HectorPerezUrbina: @Amanda, certainly. In Stardog, for example, we allow to validate 
	integrity constraints (under CWA) and usual OWL inference (under OWA), but it is necessary for the 
	user to clearly specify which things are to be taken under which semantics.    (41IK)
	[10:39] AmandaVizedom: Okay, I need to stop typing and pay attention to Hassan for a bit!    (41IL)
	[10:40] PascalHitzler: Regarding the open/closed world discussion: What is really needed are 
	languages which combine open world and closed world features, in such a way that you can decide 
	what's supposed to be closed and what's supposed to be open. The keyword sometimes used is "local 
	closed world". There's quite a bit of work under way how to do this (see e.g. the paper by Motik 
	referenced above), but the quest is not yet conclusive, in particular in practical terms.    (41IM)
	[10:40] AmandaVizedom: @PascalHitzler: Exactly!    (41IN)
	[10:41] AmandaVizedom: @Hector: Excellent. :-)    (41IO)
	[10:41] HectorPerezUrbina: @Amanda, you might find this interesting: http://docs.stardog.com/icv/    (41IP)
	[10:42] AmandaVizedom: Thanks Hector, I'll check it out.    (41IQ)
	[10:45] EnricoFranconi: Again, in my paper I argue why epistemic axioms can be very misleading. In 
	your simple example with SSN, this approach may work. But since you expect two different beahviours 
	from your data stemming form conflicting assumptions, there will always be counterexamples where 
	your get unexpected inferences.    (41IR)
	[10:46] EnricoFranconi: @Hector: really look at our paper on why you shouldn't validate integrity 
	constraints with a different semantics from the underlying ontology language.    (41IS)
	[10:46] HectorPerezUrbina: @Enrico, yes, it helps that we consider relatively unexpressive logics 
	(i.e., OWL profiles)    (41IT)
	[10:47] MarkusKroetzsch: +1 to epistemic axioms being confusing    (41IU)
	[10:47] EnricoFranconi: :-)    (41IV)
	[10:47] EnricoFranconi: Mmhh, I guess I can build some nasty counterexamples with dl-lite as well, 
	but I have to think about it.    (41IW)
	[10:48] HectorPerezUrbina: @Enrico, will do. I would say, however, that we are yet to see these 
	nasty examples in practice.    (41IX)
	[10:48] EnricoFranconi: OK.    (41IY)
	[10:48] AmandaVizedom: @EnricoFranconi: Do you have a link to your paper? I would like to understand 
	why you think that support for making assumptions explicit is inferior to being restricted to one of 
	the assumptions. ... ref. below - [11:13] EnricoFranconi: My paper on "Ontology constraints in 
	incomplete and complete data" can be found at http://iswc2012.semanticweb.org/sites/default/files/76490433.pdf    (41IZ)
	[10:51] AmandaVizedom: Epistemic axioms may be confusing, but IMHO the better way of addressing this 
	is to make clear and explicit which axioms are epistemic and what they apply to (even if as 
	metadata). Otherwise, users and modelers tend to *make* epistemic assumptions anyway, without making 
	the explicit, and sometimes slide between epistemic assumptions within the same model or set of 
	models, without being able to indicate this. This causes problems for model accuracy, usability, 
	evaluation, quality control / truth maintenance (as the model evolves), and reuse.    (41J0)
	[10:49] PeterYim: == EnricoFranconi presenting ...    (41J1)
	[10:51] SimonSpero: Hector: If every employee has a known ssn and hector does not have a known ssn 
	then hector is not an employee    (41J2)
	[10:52] HectorPerezUrbina: @Simon, that's under OWA    (41J3)
	[10:54] HectorPerezUrbina: Consider the ontology O = {1. Employee subClassOf hasSSN some SSN, 2. 
	Hector a Employee} . Under OWA, we would infer the existence of an anonymous individual, instance of 
	SSN, related to Hector via hasSSN.    (41J4)
	[10:54] HectorPerezUrbina: However, sometimes, we don't want this behavior; instead, we want the 
	reasoner to let us know that our data is invalid (because every employee must have a SSN)    (41J5)
	[10:55] HectorPerezUrbina: We can accomplish this by interpreting axiom 2 in O under CWA.    (41J6)
	[10:55] HectorPerezUrbina: sorry, axiom 1.    (41J7)
	[10:58] AmandaVizedom: @Hector: yes, and more: we may want to validate/ declare that invalid. Or, we 
	may want to identify gaps in our knowledge. Or, in more sophisticated reasoning, analyze our model 
	to identify *patterns* of missing information. The known unknowns can be very important in some applications!    (41J8)
	[11:05] HectorPerezUrbina: @Amanda, yes. In practice, people produce some RDF out of an ETL process, 
	and they need to check whether certain integrity constraints (a la DB) hold.    (41J9)
	[10:59] SimonSpero: Hector: But you leave out the axiom hasSSN(X) -> K[hasSSN(X)]    (41JA)
	[11:00] MikeBennett: OWA and CWA: it seems to me that the use case of determining whether some data 
	is valid (per @Hector above), and the use case whereby we want to reason over assertions about real 
	things in the world (not data) are two very different requirements. My hunch would be that to talk 
	about data rather than actual things, one must need the CWA?    (41JB)
	[11:03] HectorPerezUrbina: @Simon, yes, we want to stay within OWL and SWRL    (41JC)
	[11:03] HassanAitKaci: @EnricoFranconi: This is a CWA construction! :-)    (41JD)
	[10:57] AlanRector: [ref. slide#5] Shouldn't be that some ice cream is food, rather than that all 
	ice cream is food/ice cream is subset of food?    (41JE)
	[10:58] PascalHitzler: @Alan, I believe in the example, ice cream is an individual, while food is a class?    (41JF)
	[11:00] FrancescaQuattri: @EnricoFranconi: Beth Levin's work could provide a great deal of 
	inspiration for defining what is (or should be defined) subclass of what    (41JG)
	[11:00] MikeBennett: Apologies, have to leave now.    (41JH)
	[11:04] anonymous morphed into NancyWiegand    (41JI)
	[11:07] AlanRector: Apologies. I have to leave now    (41JJ)
	[11:07] PeterYim: == Q&A and open discussion now    (41JK)
	[11:08] List of members: AidaGandara, AlanRector, AliHashemi, AmandaVizedom, ChuckRehberg, 
	ConradBock, DavidMendes, DennisPierson, EnricoFranconi, ElieAbiLahoud, FrancescaQuattri, GaryGannon, 
	GenZou, HaroldBoley, HassanAitKaci, HectorPerezUrbina, HensonGraves, LeoObrst, MarkusKroetzsch, 
	MichaelGruninger, MikeBennett, NancyWiegand, OliverKutz, PascalHitzler, PatrickMaroney, PeterYim, 
	RyanHohimer, SimonSpero, SimonSpero, TaraAthan, ToddPehle, vnc2    (41JL)
	[11:09] anonymous morphed into DennisWisnosky    (41JM)
	[11:10] anonymous1 morphed into lakhdar    (41JN)
	[11:11] AmandaVizedom: @Hector, this is one type of case. But I am also thinking of another case in 
	which a user is using an ontological KB for situation awareness, risk analysis, or similar. In these 
	cases, while much of the use of the model involves reasoning about the modeled things (or digesting 
	views of a situation that are based on model), it can be an essential part of this use to also 
	(manually or automatically in side processes) identify the known unknowns and spot patterns in them. 
	This can be critical.    (41JO)
	[11:12] HectorPerezUrbina: @Amanda, yes, this sounds quite interesting/important.    (41JP)
	[11:13] EnricoFranconi: My paper on "Ontology constraints in incomplete and complete data" can be 
	found at http://iswc2012.semanticweb.org/sites/default/files/76490433.pdf    (41JQ)
	[11:13] HectorPerezUrbina: @Enrico, thank you    (41JR)
	[11:13] AmandaVizedom: @EnricoFranconi: Thanks, I will read it.    (41JS)
	[11:16] EnricoFranconi: Just do (:yourLocalProperty rdfs:subProperty :globalProperty)!    (41JT)
	[11:17] FrancescaQuattri: yup, clear    (41JU)
	[11:20] EnricoFranconi: [in response to PatrickMaroney's question on where details of 
	EnricoFranconi's work (the evaluations, in particular) can be accessed] Official link: 
	http://link.springer.com/content/pdf/10.1007/978-3-642-41335-3_7.pdf    (41JV)
	[11:20] EnricoFranconi: Unofficial link: http://users.dcc.uchile.cl/~cgutierr/papers/iswc2013.pdf    (41JW)
	[11:16] PeterYim: @EnricoFranconi - (recapping my verbal comment) it would be great to further 
	expose your work to PatHayes, and convince him and those who are working on the next iteration of 
	RDF/RDFS, so your work can be taken into consideration in that W3C standard ... [I will try to 
	forward this to PatHayes, copying you too, after the session]    (41JX)
	[11:17] EnricoFranconi: @PeterYim: thanks    (41JY)
	[11:22] SimonSpero: RDF Semantics 1.1 just went to Candidate Rec status on Nov 5th, ( last step 
	before final) http://www.w3.org/blog/news/archives/3389    (41JZ)
	[11:22] EnricoFranconi: "Work as expected" means complete & terminating in the fragment of the use case.    (41K0)
	[11:23] EnricoFranconi: So, you DO care!    (41K1)
	[11:25] MarkusKroetzsch: Sorry, I got distracted by my phone call. To clarify: in the context of 
	ontology "undecidable" = "not sufficiently studied to understand when it will work" (it's different 
	for programming and problem solving languages, where undecidability is necessary to express 
	arbitrarily complex computations/problems.)    (41K2)
	[11:26] HaroldBoley: Regarding decidable <> efficient etc., average-case complexity should be 
	considered, rather than (only) worst-case complexity.    (41K3)
	[11:26] HassanAitKaci: +1 Harold    (41K4)
	[11:26] HectorPerezUrbina: @Harold +1    (41K5)
	[11:27] EnricoFranconi: @Harold: yes, but sill in the context of complete and terminating fragments.    (41K6)
	[11:27] HectorPerezUrbina: also, so-called data complexity is quite important    (41K7)
	[11:27] EnricoFranconi: @Hector +1    (41K8)
	[11:27] PeterYim: Great session!    (41K9)
	[11:26] PeterYim: Join us again, in two weeks (Thu 2013-12-05) for the OntologySummit2014 Pre-Launch 
	Community Session, when we will collaboratively work up a program for the next OntologySummit.    (41KA)
	[11:26] PeterYim: That will be followed (on Dec-12) by session-07 of the OntologyBasedStandards 
	miniseries - "How ontologies can help with the formal specification of the natural language 
	standards" - Co-chairs: SimonSpero & KenBaclawski    (41KB)
	[11:26] PeterYim: The next event (session-04) for this RulesReasoningLP mini-series will then come up 
	on Dec-19 - "Guide to Reasoning Applications Development and Cases" - Co-chairs: HensonGraves & KenBaclawski    (41KC)
	[11:28] AmandaVizedom: Thanks, all!    (41KD)
	[11:28] HassanAitKaci: bye & thanks    (41KE)
	[11:28] EnricoFranconi: bye    (41KF)
	[11:28] PascalHitzler: thanks!    (41KG)
	[11:28] LeoObrst: Thanks, All! Very interesting session.    (41KH)
	[11:28] HectorPerezUrbina: good bye everyone    (41KI)
	[11:28] MarkusKroetzsch: Bye, thanks.    (41KJ)
	[11:28] PeterYim: -- session ended: 11:28am PST --    (41KK)
 -- end of in-session chat-transcript --    (4139)

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