DTV11 — DTV Issue: The definitions of 'starts before' and 'finishes after' are too complex

OMG Specification: Date Time Vocabulary

Version: 1.0

Title: The definitions of 'starts before' and 'finishes after' are too complex

Summary:

In clause 8.2.4, the definition of ‘time interval1 starts before time interval2’ enumerates several possible Allen relations, but what is intended can be stated more simply: There is a time interval3 that is part of time interval1 and precedes time interval2.

Similarly ‘time interval1 ends after time interval2’ is: There is a time interval3 that is part of time interval1 and follows time interval2.

Time interval1 begins time interval2 seems to be misdefined. The example says 2009 begins 2010 and that is false. The intent of this verb concept should be clarified. Similarly, in Time interval1 ends time interval2, the example that is mislabeled Definition is the only example that a business person would recognize as T1 ends T2 and that is an instance of the Allen relation: T1 finishes T2.

The Definitions of ‘time interval1 starts before time interval2’ and ‘time interval1 finishes after time interval2’ are incorrect. The definition of ‘starts before’ omits the case where time interval2 finishes time interval1, and similarly ‘finishes before’ omits the case where time interval2 starts time interval1. The definitions will be corrected as suggested.
The example “2009 begins 2010” is not valid and will be removed.