[Geysers] Help with student presentation

[Karen Webb]

 From Karen Webb
Hi gang:
    My little boy is trying to put together a presentation on how 
geysers are predicted.  My recollection is that Marler actually 
developed a formula from which the current predictive values for OF 
arose but all I've been able to find is several versions of the table 
that says "if eruption is X minutes long, predict next eruption in Y 
minutes."  Can anyone help us out with the actual math that gave rise to 
this?  Also, for the bigger geysers like Grand with longer windows, is 
the predictive interval based on a certain number of previous eruptions 
(like do they get the interval from the average of Z number of previous 
eruptions, or does it take a certain number of eruptions with a shorter 
or longer interval to prompt the VC to change this interval)?
    Thanks for any info or resources anybody has.
Karen