[Eventstudies-discussion] Class for event time

[Chirag Anand]

Hello,

The current development version (1.2) deals with event time by taking
in a data.frame of event (say) dates in the column "when" and the unit
of observation in "unit". One, this creates a confusion for the user,
and secondly, it makes harder for the phys2eventtime function to match
the dates specially when the exact event time is missing from the
observations.

In my opinion, having event time (event.list object) as a 'zoo' object
solves the matching problem. The index() of both the zoo objects, the
actual observations and event list can be used to match using
findInterval(). Since the class of the event time will be defined,
there won't be an issue dealing with say intraday or monthly data.

For this, I have thought of two solutions:

1. We keep the current API and ask the users to give us the "when"
column in the time-based class which defines the index of the main
object. phy2eventtime converts this to a zoo index directly, thus
maintaining the original time-based class.
2. We ask the user to give event.list as a zoo object directly.

The second solution, in my opinion will also eliminate the problem of
defining "unit" and "when" in the event.list object.

Thanks,

-- 
Chirag Anand
http://atvariance.in/chiraganand