You might want to look at the TEMPER dates that CDL has proposed. This
isn't a standard, but I suppose it could become one. It is designed to
handle ranges, approximate dates, etc.

   http://www.cdlib.org/inside/diglib/ark/temperspec.pdf

kc

Rebecca S. Guenther wrote:
> ISO 8601 has limited ability to express a lot of types of dates,
> especially some needed for cultural heritage objects, like those that are
> questionable, approximate, etc. Perhaps we should come up with some PREMIS
> conventions. I looked at this a few years ago in the context of some
> Dublin Core work and could dig up my notes if needed on the limitations of
> 8601. There has been little consensus on conventions for these kinds of
> uncertain dates. So it may be prudent to establish some for PREMIS perhaps
> based on what other efforts may be using.
>
> Rebecca
>
> On Fri, 16 Jun 2006, Matthew Beacom wrote:
>
>
>> Hello,
>>
>> It may be that one simply can't use ISO 8601: 2004 this way. Using
>> 9999 and 0000 to represent not "dates in the Gregorian calendar" but
>> rather a quality of open-endedness with respect to an end date or a
>> start date is logically outside of the domain of ISO 8601. Anything
>> we do would be a kluge.
>>
>> 9999 may not be the best value to mean "forever" as it would also
>> mean the year 9999. A bit far off to worry about, of course. And OOOO
>> would mean 1 BCE (or be illegal) as there is no year 0 between the
>> first year of the common era (1 CE) and the last year prior to the
>> 1st year of the CE (1 BCE).
>>
>> I think, though, that 0000 is not needed since a way to represent the
>> open-endedness of a start date is not needed. The rights related to
>> the object can't pre-date the object itself. So One can simply use a
>> practical (albeit) arbitrary start date such as the date of the
>> creation of the digital object or, if necessary, the date of the
>> original object for which the digital copy is a proxy.
>>
>> And then--for about 8000 years anyway--9999 may work perfectly well
>> being used to mean endless. But, of course, that would be a
>> non-standard use of 9999.
>>
>> Matthew Beacom
>>
>> p.s. below is the abstract for ISO 8601: 2004 from
>> http://www.iso.org/iso/en/CatalogueDetailPage.CatalogueDetail?CSNUMBER=40874&ICS1=1&ICS2=140&ICS3=30
>>
>> ISO 8601:2004 is applicable whenever representation of dates in the
>> Gregorian calendar, times in the 24-hour timekeeping system, time
>> intervals and recurring time intervals or of the formats of these
>> representations are included in information interchange. It includes
>> * calendar dates expressed in terms of calendar year, calendar
>> month and calendar day of the month;
>> * ordinal dates expressed in terms of calendar year and calendar
>> day of the year;
>> * week dates expressed in terms of calendar year, calendar week
>> number and calendar day of the week;
>> * local time based upon the 24-hour timekeeping system;
>> * Coordinated Universal Time of day;
>> * local time and the difference from Coordinated Universal Time;
>> * combination of date and time of day;
>> * time intervals;
>> * recurring time intervals.
>> ISO 8601:2004 does not cover dates and times where words are used in
>> the representation and dates and times where characters are not used
>> in the representation.
>>
>> ISO 8601:2004 does not assign any particular meaning or
>> interpretation to any data element that uses representations in
>> accordance with ISO 8601:2004. Such meaning will be determined by the
>> context of the application.
>>
>> Matthew Beacom
>>
>> Metadata Librarian
>> Yale University Library
>> 130 Wall Street P.O. Box 208240
>> New Haven, CT 06520-8240
>>
>> phone: (203) 432-4947
>> fax: (203) 432 7231
>> e-mail: [log in to unmask]
>>
>>
>
>
>

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