On Fri, 22 Jul 2011 14:16:03 -0400, Ray Denenberg, Library of Congress wrote
> From: Edward C. Zimmermann
> > Does "1960/1964-04" contain
> > - "1963"? Yes
> > - "1964"? Yes (since the precision of comparison can't ever be finer
> > than the the precision of the least precise measure).
> I'm not sure that I could sensibly explain why "1964" is within the
> "1960/1964-04" because it seems to me the question asks whether the whole
> year fits within that interval (it doesn't) not whether it overlaps.
> But I don't think we need to belabor this.
We don't need to.. but, of course, I won't hold back...
The date expression "1964" does not express the "whole year" but rather a
measurement point with precision of year. Abe Lincoln, for example, was not
murdered the whole day of 14 April 1865 but shot at an instant within that
day. Its typically given that he was shot at 22:15 and died the next day at
7:22. Was he shot the "whole" of the minute? Did he die a whole minute long?
Or, again, was it not both instants--- this time measured, resp. expressed,
In comparing two measures of two different objects with differing
precisions---- here its dates but it could be temperature, length, mass or
whatever--- one must normalize to a common precision and this ultimately is
typically the coarser of the two.
Imagine, for example, two people that measure the weight of same specimen
using different scales. One person using a good quality analytic lab balance-
-- for example readable to 0.01mg with 0.05mg repeatability--- may read
1.0146g while the other using a much cruder scale readable to gramms may
read only 1 gram. 1.0146g is not a greater measure than the 1g. Both have
measured the same sample but at different precisions. The weights must then
be "the same".
Measuring another specimen the first reads on their analytic balance
1.0370g. The second person reads 1 gram. At the precision of the lab balance
the second sample is heavier than the first but at the precision of the
crude scale the two weigh the same.
Turing now to dates the date "1964-04" if measured in year precision would
yield "1964". In month precision "1964-04" is before "1964-06" but in year
precision they are "the same" just as two babies born on the same day but at
different times share the same birthday.
> > With a higher level of (measurement) precision, of course, it might
> > turn out that the date expressed as "1964" in the comparison was really
> > "1964-05- 12T12:30" and this NOT in the interval but is it really the
> > same comparison?
> You definitely lost me there, but similarly I don't think we need to
See the above.. and perhaps think about increasingly precise balances...
Edward C. Zimmermann, NONMONOTONIC LAB
Basis Systeme netzwerk, Munich Ges. des buergerl. Rechts