Off topic: Why a 2 in smoothing factor of XAverage?

[Jack Griffin <jack_2231@xxxxxxxxx>]

I was just noticing that there are two different
XAverage functions in Tradestation.  One has a
smoothing function of 2/(1+Length) while the other
("orginal version") has a smoothing function of
1/Length.  It seems the conventional exponential
moving average is the former (with the 2).  

Does anyone happen to know who decided to put that 2
in there and why?  Just curious and thought I'd ask
old timers on the list in case they has a nice story
to tell.

Jack