[Crm-sig] A question about relations between time intervals with fuzzy borders

[Bernhard Schiemann]

Dear all,

 In CRM, E2 Temporal Entities are located on the timeline by E53
 Time-Spans, which may have fuzzy borders.  At the same time, Allen's
 interval relations are defined on E2 through the properties
 P114-P120, and in their scope notes it is stated that they "can be
 calculated".  However, Allen's interval relations and inference rules
 are only well-defined on intervals with "clear cut" borders, not with
 fuzzy ones.

 Currently there seems to be some unclarity and ambiguity regarding
 the right classification of and inferencing over E2 and P114-P120.
 Some examples are illustrated in the attached figure: While the
 relationship between X2 and X3 can be clearly classified as P117(I)
 occurs during, the situation is totally unclear in the case of X4 and
 X5.  Even for X1 and X2 three properties --- P118 overlaps in time
 with, P119 meets in time with and P120 occurs before --- (may) hold,
 dependending on the the view on the fuzzy borders.  Allen's
 relations, though, are thought of as mutually exclusive.

 Obviously, the problem lies in the interaction of the fuzzy borders
 and Allen's relations: which temporal extent should be used for
 calculation?  The minimal or the maximal extent or something in
 between?

 One possible solution could be to ignore the fuzziness of E52
 Time-spans and just annotate the relations which can be trusted
 (minimal extent).  Has anybody an idea about a best practice about
 the P114-P120 relations?

 So, to sum up, the main problem is to compute Allen's relations on
 time-spans with fuzzy borders. To the best of our knowledge Allen
 himself did not make a suggestion for this kind of problem.  Does
 anybody someone know about publications on this problem?

Best regards,

Martin Scholz, Dipl-Inf.

 Artificial Intelligence Division
 Department of Computer Science
 University of Erlangen-Nuremberg
 Haberstr. 2
 91058 Erlangen

 martin.scholz at informatik.uni-erlangen.de

-- 
*************************************************************
Bernhard Schiemann, Dipl. Ing.
Artificial Intelligence Division
Department of Computer Science
University of Erlangen-Nuremberg
Haberstr. 2, D-91058 Erlangen, Germany

Tel.:  +49-9131-85-28984
Fax :  +49-9131-85-28986
Email: schiemann at informatik.uni-erlangen.de
http://www8.informatik.uni-erlangen.de/inf8/en/schiemann.html
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