Hi Tara,
Yes, I also think we need both. That is why I propose to use a more general <Collection> which can be typed (type="..") with different sorts.
1. Is there a default selection between continuous and discrete timescale that would resolve this ambiguity?
Yes, the default one is a time interval semantics.
(On a side note: this distinction in interval semantics and point in time semantics is important as it avoids ambiguity in the algebra operators for complex events, as we have shown in our interval base event calculus semantic for complex event processing)
2. According to the schema, the content model appears to be essentially
unrestricted: <ruleml:Time><ruleml:content>...anything...</ruleml:content></ruleml:Time>
No, the main content type is an <arg> with e.g. Ind, Data, Var or Expr or a slotted representation with a <slot>. Therefore it reuses the content model of <arg> and <slot> from <Atom>.
The additional choice of a <content> role tag with unrestricted XML content model is an extension point of the Reaction RuleML syntax, which allows embedding one of the many existing XML serializations for time data from the various communities which deal with time.
3. Is it possible to use the element <ruleml:Time> to describe a timepoint that is 6 months after some named timepoint?
Yes, this is a temporal operation
<After>
<ruleml:Time key="#t1">...</ruleml:Time>
<ruleml:Time><ruleml:Data xsi:type="xs:duration">6M</ruleml:Data></ruleml:Time>
</After>
BTW, I just encountered that I had sent my regrets for the last telecon on Wednesday not from my gmx address but from my university address which apparently seems to be rejected by the mailing list. Sorry, for that. I attach it again with the example version which preserves the advantages and conveniently combines it with the rest of RuleML.
-Adrian
-----Original Message-----
From: [mailto:] On Behalf Of Tara Athan
Sent: Samstag, 20. Oktober 2012 17:26
To:
Subject: Re: [legalruleml] Time Instants or Time Points
Thanks Adrian.
In legal applications, it appears to me that both discrete and continuous of timescales are needed.
When describing an observation of the time at which a physical event takes place (e.g. publication), then a discrete timescale is appropriate because this captures the fact that all observations have limited precision. Discrete timescales capture this uncertainty as intervals in time in a similar way that significant digits are used to record numerical measurements in general, (except that the time interval is assumed to lie on the future side of the time observation rather than being centered on the measurement as is done with significant digits.)
When defining a fiat event (e.g start of enforceability), then a continuous timescale may be appropriate because the definition can be made with infinite precision.
I have included the <ruleml:Time> element in the LegalRuleML schema, but so far I have only implement a restricted content model of the form
<ruleml:Time><ruleml:Data
xsi:type="xs:dateTime>2012-10-02T10:45:34-00:00</ruleml:Data></ruleml:Time>
I have a couple of questions:
1. Based on what you say below, the interpretation of this construct appears to be ambiguous because there is no @type on the Time element.
If a discrete timescale is adopted, this would represent an interval of length one second.
If a continuous timescale is adopted, this would be interpreted as a time instant, in particular the beginning of the time interval described by <ruleml:Data xsi:type="xs:dateTime>2012-10-02T10:45:34-00:00</ruleml:Data>
Is there a default selection between continuous and discrete timescale that would resolve this ambiguity?
Since the argument
<ruleml:Data xsi:type="xs:dateTime>2012-10-02T10:45:34-00:00</ruleml:Data>
already denotes a temporal entity, a time period of length 1 second (the value space of xs:dateTime is actual time periods and is based on ISO 8601), I would expect the default, if there is one, to be the discrete timescale.
2. I would like to include more of the content model for this element as defined in the Reaction RuleML schema http://www.csw.inf.fu-berlin.de/RRML1.0/xsd/modules/time_module.xsd
but the interpretation of this more general syntax is not clear to me.
According to the schema, the content model appears to be essentially
unrestricted:
<ruleml:Time><ruleml:content>...anything...</ruleml:content></ruleml:Time>
Is it possible to use the element <ruleml:Time> to describe a timepoint that is 6 months after some named timepoint?
( <ruleml:Time key="#t1">...</ruleml:Time> )
Tara
On 10/20/2012 9:24 AM, Adrian Paschke wrote:
