```Ed--
By your view, 1960/1969 (and 1960--1969) is "an interval with precision of
year", while 196x is "the decade of the 60s, with precision of decade".

The problem I see is that "decade" is pretty specialized. I mean, suppose
instead you have the interval 1958/1969 (equivalent to 1958--1969),
similarly, in your terms, "an interval with precision of year" but there is
no corresponding x representation.

So how useful is this x representation really (when it can only represent
intervals of powers of ten), and how useful is the "precision of decade"?

I would just as well then leave out the x notation alltogether.  Personally
I think it is more useful applied as "discrete years", but that's just my
view, and as Simon suggests, it's best to avoid notatations that people want
to use in divergent ways.

--Ray

> [mailto:[log in to unmask]] On Behalf Of Edward C. Zimmermann
> Sent: Tuesday, December 14, 2010 3:49 AM
> Subject: Re: [DATETIME] 'x' notation - Discrete years vs. interval
>
> On Mon, 13 Dec 2010 17:57:56 -0500, Denenberg, Ray wrote
> > (See also related posting "multiple dates".)
> >
> > On the issue of what does '196x' mean - does it mean "all of the
> > discrete years 1960 through 1969", as I proposed, or should it mean,
> > as Ed proposes, the continuous interval, and thus the decade, the
> 1960s?
>
> Actually... I suggested that 196x is 1960s as a decade with the
> precision of decade.
>
> > I don't see too much harm in Ed's proposal, "continuous interval".
>
> A "continuous interval" covering a unit X in precision X is nothing
> more than, I'd suggest, a discrete date with a precision of X.
>
>
> >  And, from looking at recent discussion, my impression is that nobody
> > (besides Ed) cares much about the issue.
>
> I'm not sure.. Even if people don't quite grasp why I still would
> suggest there is nothing to loose by decoupling precision and accuracy-
> -- as we do in all scientific measurements.
>
>
> >
> > I do see a the following issues, though.
> >
> > first, it would follow that 19xx means 20th century. Or actually no,
> I
> > suppose it wouldn't really, since a century is defined to begin at
> > year 1 - the 20th century begins with year 1901. (This is as opposed
> > to the definition of a decade - a decade begins with a year ending in
> > 0.) The point I'm getting to is that there already is a syntax for
> > century prescribed in ISO 8601: '19' means 20th centtury (there is no
> > corresponding similar syntax for decade).  So, we would need
>
> Correct. ISO 8601 has a large number of implicit precisions. 19 means
> 20th century, 1982 is in year precision, 1982-12 is in month precision,
> 1882-W12 is in week precision,  1981-12-12 is in day precision..
>
>
> > to be very careful about all this. 196x would mean the decade of the
> > 1960s. 19xx would mean the interval 1900 through 1999 but it would
> not
> > mean the 20th century. Perhaps this really isn't a problem at all,
> > just a cautionary note.
> >
> > Second, we would then have three (!) syntaxes for an interval (for a
> > decade, for example).  The 1960s would be (1) 1960/1969 (2) 1960-
> > -1960 (3) 196x.
>
> 1) 1960/1969 is an interval with precision of year.
> 2) I'm not sure what it is
> 3) Its, I've suggested, the decade of the 1960s with the precision of
>
> 19xx and 19 are, I think, semantically equivalent.
>
>
> > Third, there is a possible utility in allowing the x notation for
> > multiple dates, but see related posting "multiple dates".
> >
> > Thoughts, please.
> >
> > --Ray
>
>
> --
>
> Edward C. Zimmermann, NONMONOTONIC LAB
> Basis Systeme netzwerk, Munich Ges. des buergerl. Rechts Office Leo
> (R&D):
>   Leopoldstrasse 53-55, D-80802 Munich,
>   Federal Republic of Germany
> http://www.nonmonotonic.net
> Umsatz-St-ID: DE130492967
```