Subject: Dates and Time-Sensitive Analysis Applications...

From: "Bob Wyman" <[email-masked]>
Date: Wed, 4 Aug 2004 21:17:16 -0400

I realize that the date discussion moratorium is still in effect,
however, I'd like to point out some uses of dates that I don't think have
been considered in the various discussions so far. This is "requirements"
and "background" data, not moratorium-prohibited advocacy...
	Most of the discussion of dates seems to have focused only on dates
as used in ordering entries within feeds, displays or lists. However, there
are other very interesting uses of dates. For instance, there are a number
of applications that explicitly seek "new" entries where "new" means
something like "fresh or recent" rather than just "different from what was
seen before" or "later than a previous version." Such applications include:
	1. Topic Detection and Tracking (TDT)[0] apps: (e.g. popdex.com[1],
daypop.com's word[2] or news bursts[3], etc.)
	2. Time-sensitive Ranking systems: (e.g Daypop's TopWeblogs[4] or
the Link Ranks[5] of PubSub.com )
	These applications all rely on some kind of "time-weighted" scoring
in an attempt to measure recent activity. Thus, it is important for them to
be able to determine not just what is a unique entry but also when the entry
was created. Additionally, it is important to be able to identify the date
of an entry on a scale which is global (i.e. time zone and use of UTC *is*
important). 
	I think that applications like those mentioned above are likely to
become important tools in helping people deal with and understand the
massive number of entries in the Blogosphere. 
	A specific example of a use for such time-sensitive data can be
found at PubSub.com, where we now go beyond simply rating the various blogs
with our Link Ranks, we also allow users to use Link Ranks as a means of
filtering the set of blogs against which their subscriptions are matched.
You can, for instance, say that you only want to receive blog entries that
come from those sources which are in the top 1, 2, 5, 10, 25 or 75
percentile of blogs according to Link Rank. Given that Link Ranks are highly
date-sensitive; this means that the more you restrict your subscription, the
more likely you'll be getting content from "hot" blogs. But, the system only
works if we can determine the difference between a new and an old posting. 
	Any of the TDT applications are going to have a similar reliance on
accurate date information. The more imprecise the information about when an
entry was created, issued, modified or whatever, the harder it is to be
precise about what is topical and current. Thus, if we can't get a good
solution to the date problem, we're going to find that this class of
application will be much less useful to users than it otherwise might be.
	Anyway, there is much more to dates than simply providing a means of
ordering results in an aggregator window...

		bob wyman

[0] http://www.nist.gov/speech/tests/tdt/index.htm
[1] http://popdex.com/
[2] http://www.daypop.com/burst/
[3] http://www.daypop.com/newsburst/
[4] http://www.daypop.com/blogrank/
[5] http://www.pubsub.com/linkranks.php

---

From: "Jon Meyer" <[email-masked]>
Date: Wed, 4 Aug 2004 21:52:07 -0400

On a similar vein, is anyone else out there interested in applying Atom to
calendrical events, e.g. a "Whats happening" blog, where entries in the feed
correspond to events that will happen? This is similar to future-posting,
except you need two dates (start and end).

Jon

-----Original Message-----
From: [email-masked] [mailto:[email-masked]]
On Behalf Of Bob Wyman
Sent: Wednesday, August 04, 2004 9:17 PM
To: 'Atom syntax'
Subject: Dates and Time-Sensitive Analysis Applications...

		bob wyman

---

From: "Bob Wyman" <[email-masked]>
Date: Thu, 5 Aug 2004 10:42:40 -0400

Jon Meyer wrote:
> is anyone else out there interested in applying Atom to
> calendrical events, e.g. a "Whats happening" blog,
	I think that announcing and maintaining information on events will
become an important use for Atom once we're finished working out the blog
related issues. 
	My hope is that folk don't go off trying to reinvent the wheel but
will, instead, try to stay as close as possible to iCalendar[1], vCard[2]
and EventsML[3] when they do this. (Note: EventsML is produced by the
IPTC[6], the same folk that maintain the NewsML format.) Also, given the
frequently noted similarities between the Atom API and WebDAV[4], one should
probably give some thought to Linda Dusseault's proposed CalDAV extensions
to WebDav[5].
	My personal belief is that every theater (dance, ballet, music,
movie, etc.) every organization, every municipal, state and federal
government, etc. will one day syndicate detailed information on all of their
public events. This will ensure the widest possible dissemination of event
information -- something which is not the case today.

		bob wyman

[1] http://www.ietf.org/html.charters/calsch-charter.html
	(See list of RFC's and ID's at bottom of page above)
[2] http://www.ietf.org/rfc/rfc2739.txt
[3] http://www.iptc.org/EventsML/
	http://groups.yahoo.com/group/eventsml/
[4] http://www.ietf.org/html.charters/webdav-charter.html
[5] http://www.rfc-editor.org/internet-drafts/draft-dusseault-caldav-01.txt
[6] http://www.iptc.org/pages/index.php

---

From: Libby Miller <[email-masked]>
Date: Thu, 5 Aug 2004 15:52:31 +0100 (BST)

> will, instead, try to stay as close as possible to iCalendar[1], vCard[2]

note that we have been working on a test-case-based version of 
iCalendar in RDF:

http://www.w3.org/2002/12/cal/
http://esw.w3.org/topic/RdfCalendarDocumentation
http://esw.w3.org/topic/RdfCalendarPresentation
http://planb.nicecupoftea.org/archives/000769.html

If there's a clear demand for it we would be interested in doing an XML 
profile for this work. We're also thinking right now about documentation 
for it, so suggestions are welcome (we're aware that the documentation 
isn't sufficient right now).

iCalendar (RFC 2445) isn't suitable for all events, but it is almost 
sufficient for conferences, cinema listings etc and is used in most 
personal information management tools, which is why round-tripping from 
an XML format of icalendar to iCalendar is important (we do this).

Libby

---

From: Martin Duerst <[email-masked]>
Date: Fri, 06 Aug 2004 05:57:51 +0900

I have just attended the meeting of the calsch WG at the IETF
in San Diego. Participants, mainly implementers of iCalendar,
expressed that there is a need for a new version of the spec
that most probably cuts out certain things that have shown to
not work well. Journaling and recurring events were mentioned.

Regards,    Martin.

At 15:52 04/08/05 +0100, Libby Miller wrote:

>note that we have been working on a test-case-based version of iCalendar 
>in RDF:
>
>personal information management tools, which is why round-tripping from an 
>XML format of icalendar to iCalendar is important (we do this).
>
>Libby
>