- From: Graham Klyne <GK@ninebynine.org>
- Date: Mon, 20 Jun 2011 11:22:41 +0100
- To: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- CC: public-prov-wg@w3.org
It seems we understand the phrase "integral to identity" somewhat differently, so that's a different reason not use it as part of the definitions of "things" and "invariant views". The more you say, the more room there is for disagreement ... #g -- Luc Moreau wrote: > Hi Simon and Graham, > > I added a response to Graham's comment on invariant property and identity. > See http://www.w3.org/2011/prov/wiki/ConceptInvariantViewOnThing#Comments > > Cheers, > Luc > > On 06/19/2011 12:18 PM, Simon Miles wrote: >> Graham, >> >> OK, thanks for the clarification. I agree with your point, and am also >> sympathetic to your discomfort with everything invariant being >> "integral to identity". >> >> Thanks, >> Simon >> >> >> On 17 June 2011 23:00, Graham Klyne<GK@ninebynine.org> wrote: >> >>> Simon Miles wrote: >>> >>>> Graham, Stian, all, >>>> >>>> I might be confused, but this seems a more complex model than the one >>>> proposed by Jim and Luc. Why do we need to both a Dynamic Resource >>>> and a View Resource? I can't see any meaningful difference between >>>> them either in Graham's definition or Stian's (helpful) concrete >>>> example. What is the point of saying anything about a mutable >>>> property, e.g. "content of DynamicResource i0", when any assertion of >>>> a mutable property's value will not always hold anyway? >>>> >>> Speaking for myself... I used the terms "Dynamic" and "View" as >>> labels to >>> distinguish their roles in the structure given. I would not choose >>> to model >>> them as different types. >>> >>> My point, expressed in terms of Stian's example, is that the notion >>> we have been >>> calling IVP is present in the viewOf relation rather than inherent in >>> the >>> resources themselves. This was my point, which I think is also at >>> the heart of >>> the proposal by Jim and Luc. >>> >>> I happen to think that the definition as proposed in the wiki at >>> http://www.w3.org/2011/prov/wiki/ConceptInvariantViewOnThing#ACCEPTED_at_teleconference_2011-06-16 >>> >>> is over-specified (I've added some comments there). But having >>> expressed that >>> reservation, I'm content to let them stand pro tem for the purposes >>> of discussion. >>> >>> #g >>> -- >>> >>> >>> >>>> On 16 June 2011 15:39, Stian Soiland-Reyes >>>> <soiland-reyes@cs.manchester.ac.uk> wrote: >>>> >>>>> On Tue, Jun 14, 2011 at 12:09, Graham Klyne<GK@ninebynine.org> wrote: >>>>> >>>>> >>>>>> Suppose that the "Dynamic resource has a number of different >>>>>> observable >>>>>> properties, some of which do not change over time, and others >>>>>> which do. >>>>>> Then the View resource would be a resource for with a similar >>>>>> set of >>>>>> properties such that do not change over time, but correspond to >>>>>> the dynamic >>>>>> resource properties at a given time (including properties that do >>>>>> not change >>>>>> over time). If the Dynamic resource does not change over time, >>>>>> then it may >>>>>> also serve as its own view resource: the has view property can be >>>>>> reflexive. >>>>>> >>>>>> The provenance resource is an assertion about the properties of >>>>>> the view >>>>>> resource. I believe the key requirement that we try to capture is >>>>>> that the >>>>>> properties about which the provenance resource makes assertions are >>>>>> invariant - there is no assertion in the provenance resource which >>>>>> is not >>>>>> always true of the view resource. >>>>>> >>>>> This is a very beautifully simple model which I think we should keep >>>>> in mind before digging too much into the exciting discussions. >>>>> >>>>> >>>>> >>>>> "simplified" for the File example: >>>>> >>>>> >>>>> :i0 a :DynamicResource ; >>>>> :name "/home/towns.txt" ; >>>>> :content [ :bytes "" ] ; >>>>> :creator :Alice . >>>>> >>>>> >>>>> :i0View a :ViewResource ; >>>>> :viewOf :i0 ; >>>>> :name "/home/towns.txt" ; >>>>> :creator :Alice . >>>>> >>>>> >>>>> # Metadata stored in filesystem >>>>> :i0Provenance a :ProvenanceResource ; >>>>> :provenanceOf :i0View ; >>>>> :account :FileSystem ; >>>>> :processes ( >>>>> [ :agent :Alice ; >>>>> :location :server1 ; >>>>> :process :fileCreation ; >>>>> :time "2011-06-15 18:00:01 UTC" ] >>>>> ) . >>>>> >>>>> # however the log file claims the file was created on her workstation >>>>> (not server), and 1 second later (clocks out of sync?) >>>>> >>>>> :i0Provenance2 a :ProvenanceResource ; >>>>> :provenanceOf :i0View ; >>>>> :account :ServerLogFile ; >>>>> :processes ( >>>>> [ :agent :Alice ; >>>>> :location :AliceWorkstation; >>>>> :process :fileCreation ; >>>>> :time "2011-06-15 18:00:02 UTC" ] >>>>> ) . >>>>> >>>>> >>>>> >>>>> ### New graph - Content changed >>>>> >>>>> :i0 a :DynamicResource ; >>>>> :content [ :bytes "New York\nLos Angeles\n" ] ; >>>>> :name "/home/towns.txt" ; >>>>> :creator :Alice ; >>>>> :readBy (:Alice :Bob :Charles :David) >>>>> >>>>> >>>>> :i2 a :ViewResource ; >>>>> :viewOf :i0 ; >>>>> :name "/home/towns.txt" ; >>>>> :creator :Alice ; >>>>> :content [ :bytes "New York\nLos Angeles\n" ] . >>>>> >>>>> :i2Provenance a :ProvenanceResource ; >>>>> :provenanceOf :i2 ; >>>>> :account :FileSystem ; >>>>> :processes ( >>>>> [ :agent :Alice ; >>>>> :location :server1 ; >>>>> :process :fileCreation ; >>>>> :time "2011-06-15 18:00:03 UTC" ] >>>>> # Lost as :FileSystem metadata only keeps last-modified >>>>> # [ :agent :Alice ; >>>>> # :location :server1 ; >>>>> # :process :fileWrite ; >>>>> # :time "2011-06-15 18:00:03 UTC" ] >>>>> [ >>>>> # :agent :Bob; - not recorded as only owner/creator is kept >>>>> :location :server1 ; >>>>> :process :fileWrite ; >>>>> :time "2011-06-15 18:14:12 UTC" ] >>>>> ) . >>>>> >>>>> >>>>> So say there are additional mutable properties such as :readBy above - >>>>> would you consider those propagating into the view as mutable >>>>> properties? There could be another view over :i2 for the file before >>>>> it was read by Charles, where :readBy is an immutable property. >>>>> >>>>> The example graph above does not distinguish between mutable and >>>>> immutable properties - perhaps we shouldn't as they could be difficult >>>>> to find, identify and measure. >>>>> >>>>> Here :readBy is not kept by neither the log file or file system and is >>>>> a kind of conceptual property - it could be discovered by simply >>>>> asking everyone who could have read it, or inferred from traced file >>>>> usage, like if its sent in an email. >>>>> >>>>> -- >>>>> Stian Soiland-Reyes, myGrid team >>>>> School of Computer Science >>>>> The University of Manchester >>>>> >>>>> >>>>> ______________________________________________________________________ >>>>> This email has been scanned by the MessageLabs Email Security System. >>>>> For more information please visit http://www.messagelabs.com/email >>>>> ______________________________________________________________________ >>>>> >>>>> >>>> >>>> >>>> >>> >>> ______________________________________________________________________ >>> This email has been scanned by the MessageLabs Email Security System. >>> For more information please visit http://www.messagelabs.com/email >>> ______________________________________________________________________ >>> >>> >> >> >> >
Received on Monday, 20 June 2011 11:44:12 UTC