On the time model

Hi all.
Unfortunately, the microphone seemed to stop working during the Conference
Call. Therefore, I was not able to intervene.

This is my major concern about the representation of events, w.r.t. time.
My opinion is that events should report things that happen, not facts.
Therefore, the sense of the time interval would change, becoming unrelated
to the semantics of the reported fact. In other words, the time interval
would not refer to the time range in which the reported fact still holds
true, but rather to the time given to event consumers to process the event
before it expires.

To clarify my position:
1) Events happen, facts remain. Therefore, facts could be considered as
infrequently changing.
2) What if we have recurring activities? Say, from November the 11th, e.g.,
every day from 00:30 to 04:30 the Metro service stops. Is this an event
that recurs every day, from Nov 11 onwards, or rather one event occurring
on Nov 11 and establishing the rule, valid forever? The
fact-reporting-interpretation of events would lead to the second option.
However, this would lead to the necessity of defining periodicity for time
intervals -- which goes beyond the scope of our group, let alone
overcomplicating the model. The happening-oriented approach would allow for
the first option and a less complicated model.
3) As far as we decided, we have no alteration of preceding events.
Therefore, an event like "Claudio - lives in - Vienna" is forever true,
until a new event amends it. However, if a new event comes ("Claudio -
lives in - London"), whereas the preceding was without an ending time, we
would have an inconsistency: an event contradicts another, and there is no
clear way to establish which is saying the truth. Instead, "Claudio - moves
to - Vienna" and "Claudio - moves to - London" would make sense, as the
start-time and end-time would refer to the time where the event is still
processable. After the end-time expires, we might think of some
consequences, such as inferring and storing that Claudio lives in Vienna,
e.g. This would be related to reasoning, and disregarding the data model.

​Have a nice weekend.​
​Best regards,
Claudio​
-- 
Dr. Claudio Di Ciccio
WU Vienna
Institute for Information Business
Building D2, Entrance C, 3rd Floor
Welthandelsplatz 1, 1020 Vienna, Austria

Email: claudio.di.ciccio@wu.ac.at
Phone: +43 1 31336 5222