Re: GSC 00445-01993

[aah@nofs.navy.mil]

Michael K. wrote:
>Actually, what I mean is, in the period analysis graph that shows the 
>possible periods, the very bottom of a given possible period has never 
>been a period that works. After reading the article about period analysis,
>  it would seem that the periods that seem most likely are based on a 
>mathematical algorithm and would, in fact, be the best possible choices. 

That makes more sense; looking at your web site, I only saw
light curves.
  As John G. and Chris L. mention, these period determinations
are analytic and similar to least squares.  This means that
visual inspection may show that the mathematically best fit actually doesn't
give a reasonable light curve (the computer doesn't know what
kind of light variation you are looking for); you need to usually
inspect the top three peaks and sometimes refine the period a
bit more by hand or by data selection.
  Note that if you do 'slide' the graph a bit, then you need to
revise the error value since that is what AVE analytically determined
and now you are using a different selection method.  I usually use
the AVE error and the error from the difference between AVE's period
and your eyeball period, and add the errors in quadrature.
Arne