2. Nate Hayes wrote;
> The proper/improper property of Kaucher intervals coincides with the
> existential/universal property of modal intervals and the +/- property
> of
> directed intervals. So the following table summarizes standard
> interpretations:
>
> [a,b] [b,a] Description
> proper improper Kaucher intervals (Kaucher, Goldsztejn,
et. al.)
> existential universal Modal intervals (M. Sainz, Gardenes, et.
> al.)
> + - Directed intervals (Popova, Markov, et.
> al.)
The discussion in Section 5 of
A. Neumaier,
Computer graphics, linear interpolation, and nonstandard intervals,
http://www.mat.univie.ac.at/~neum/papers.html#nonstandard
(contains the most recent version from January 3, 2009)
shows that no deviation from the proposed notation standard is needed to
discuss nonstandard intervals.